release 3.4.1

(see issue #824)

.github/workflows/ci.yml

@@ -9,6 +9,14 @@ on:
       - '*'
     tags:
       - '[0-9]*'
+    paths-ignore:
+      - '**.md'
+      - '.*'
+      - '**/.settings/**'
+      - 'flatlaf-core/svg/**'
+      - 'flatlaf-testing/dumps/**'
+      - 'flatlaf-testing/misc/**'
+      - 'images/**'
 
 jobs:
   build:
@@ -19,28 +27,28 @@ jobs:
         # test against
         # - Java 8 (minimum requirement)
         # - Java LTS versions (11, 17, ...)
-        # - lastest Java version(s)
+        # - latest Java version(s)
         java:
           - 8
           - 11  # LTS
           - 17  # LTS
-          - 19
+          - 21  # LTS
         toolchain: [""]
         include:
-          - java: 17
-            toolchain: 20  # latest
+          - java: 21
+            toolchain: 22  # latest
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
-      - uses: gradle/wrapper-validation-action@v1
+      - uses: gradle/wrapper-validation-action@v2
         if: matrix.java == '8'
 
       - name: Setup Java ${{ matrix.java }}
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@v4
         with:
           java-version: ${{ matrix.java }}
-          distribution: temurin  # Java 8, 11 and 17 are pre-installed on ubuntu-latest
+          distribution: temurin  # Java 8, 11, 17 and 21 are pre-installed on ubuntu-latest
           cache: gradle
 
       - name: Check with Error Prone
@@ -51,7 +59,7 @@ jobs:
         run: ./gradlew build -Dtoolchain=${{ matrix.toolchain }}
 
       - name: Upload artifacts
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         if: matrix.java == '11'
         with:
           name: FlatLaf-build-artifacts
@@ -71,10 +79,10 @@ jobs:
       github.repository == 'JFormDesigner/FlatLaf'
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Setup Java 11
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@v4
         with:
           java-version: 11
           distribution: temurin  # pre-installed on ubuntu-latest
@@ -107,10 +115,10 @@ jobs:
       github.repository == 'JFormDesigner/FlatLaf'
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Setup Java 11
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@v4
         with:
           java-version: 11
           distribution: temurin  # pre-installed on ubuntu-latest

.github/workflows/fonts.yml

@@ -13,6 +13,8 @@ on:
             - 'flatlaf-fonts/**'
             - '.github/workflows/fonts.yml'
             - 'gradle/wrapper/gradle-wrapper.properties'
+            - '!**.md'
+            - '!**/.settings/**'
 
 jobs:
     Fonts:
@@ -30,10 +32,10 @@ jobs:
             github.repository == 'JFormDesigner/FlatLaf'
 
         steps:
-            - uses: actions/checkout@v3
+            - uses: actions/checkout@v4
 
             - name: Setup Java 11
-              uses: actions/setup-java@v3
+              uses: actions/setup-java@v4
               with:
                   java-version: 11
                   distribution: temurin  # pre-installed on ubuntu-latest

.github/workflows/natives.yml

@@ -13,6 +13,8 @@ on:
             - 'flatlaf-natives/**'
             - '.github/workflows/natives.yml'
             - 'gradle/wrapper/gradle-wrapper.properties'
+            - '!**.md'
+            - '!**/.settings/**'
 
 jobs:
     Natives:
@@ -20,17 +22,18 @@ jobs:
             matrix:
                 os:
                     - windows
+                    - macos
                     - ubuntu
 
         runs-on: ${{ matrix.os }}-latest
 
         steps:
-            - uses: actions/checkout@v3
+            - uses: actions/checkout@v4
 
-            - uses: gradle/wrapper-validation-action@v1
+            - uses: gradle/wrapper-validation-action@v2
 
             - name: Setup Java 11
-              uses: actions/setup-java@v3
+              uses: actions/setup-java@v4
               with:
                   java-version: 11
                   distribution: temurin
@@ -42,7 +45,7 @@ jobs:
               run: ./gradlew build-natives --no-daemon
 
             - name: Upload artifacts
-              uses: actions/upload-artifact@v3
+              uses: actions/upload-artifact@v4
               with:
                   name: FlatLaf-natives-build-artifacts-${{ matrix.os }}
                   path: |

.github/workflows/pr-snapshots.yml

@@ -0,0 +1,37 @@
+# https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions
+
+name: PR Snapshots
+
+on:
+  pull_request:
+    paths-ignore:
+      - '**.md'
+      - '.*'
+      - '**/.settings/**'
+      - 'flatlaf-core/svg/**'
+      - 'flatlaf-testing/dumps/**'
+      - 'flatlaf-testing/misc/**'
+      - 'images/**'
+
+jobs:
+  snapshot:
+    runs-on: ubuntu-latest
+    if: github.repository == 'JFormDesigner/FlatLaf'
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup Java 11
+        uses: actions/setup-java@v4
+        with:
+          java-version: 11
+          distribution: temurin  # pre-installed on ubuntu-latest
+          cache: gradle
+
+      - name: Publish PR snapshot to oss.sonatype.org
+        run: >
+          ./gradlew publish -PskipFonts -Dorg.gradle.internal.publish.checksums.insecure=true -Dorg.gradle.parallel=false
+          -Pgithub.event.pull_request.number=${{ github.event.pull_request.number }}
+        env:
+          OSSRH_USERNAME: ${{ secrets.OSSRH_USERNAME }}
+          OSSRH_PASSWORD: ${{ secrets.OSSRH_PASSWORD }}

CHANGELOG.md

@@ -1,6 +1,165 @@
 FlatLaf Change Log
 ==================
 
+## 3.4.1
+
+#### Fixed bugs
+
+- SplitPane: Update divider when client property `JSplitPane.expandableSide`
+  changed.
+- TabbedPane: Fixed swapped back and forward scroll buttons when using
+  `TabbedPane.scrollButtonsPlacement = trailing` (regression in FlatLaf 3.3).
+- Fixed missing window top border on Windows 10 in "full window content" mode.
+  (issue 809)
+- Extras:
+  - `FlatSVGIcon` color filters now support linear gradients. (PR #817)
+  - `FlatSVGIcon`: Use log level `CONFIG` instead of `SEVERE` and allow
+    disabling logging. (issue #823)
+  - Added support for `JSplitPane.expandableSide` client property to
+    `FlatSplitPane`.
+- Native libraries: Added API version check to test whether native library
+  matches the JAR (bad builds could e.g. ship a newer JAR with an older
+  incompatible native library) and to test whether native methods can be invoked
+  (some security software allows loading native library but blocks method
+  invocation).
+- macOS: Fixed crash when running in WebSwing. (issue #826; regression in 3.4)
+
+#### Incompatibilities
+
+- File names of custom properties files for nested Laf classes now must include
+  name of enclosing class name. E.g. nested Laf class `IntelliJTheme.ThemeLaf`
+  used `ThemeLaf.properties` in previous versions, but now needs to be named
+  `IntelliJTheme$ThemeLaf.properties`.
+
+
+## 3.4
+
+#### New features and improvements
+
+- FlatLaf window decorations (Windows 10/11 and Linux): Support "full window
+  content" mode, which allows you to extend the content into the window title
+  bar. (PR #801)
+- macOS: Support larger window title bar close/minimize/zoom buttons spacing in
+  [full window content](https://www.formdev.com/flatlaf/macos/#full_window_content)
+  mode and introduced "buttons placeholder". (PR #779)
+- Native libraries:
+  - System property `flatlaf.nativeLibraryPath` now supports loading native
+    libraries named the same as on Maven central.
+  - Published `flatlaf-<version>-no-natives.jar` to Maven Central. This JAR is
+    equal to `flatlaf-<version>.jar`, except that it does not contain the
+    FlatLaf native libraries. The Maven "classifier" to use this JAR is
+    `no-natives`. You need to distribute the FlatLaf native libraries with your
+    application.
+    See https://www.formdev.com/flatlaf/native-libraries/ for more details.
+  - Improved log messages for loading fails.
+- Fonts: Updated **Inter** to
+  [v4.0](https://github.com/rsms/inter/releases/tag/v4.0).
+- Table: Select all text in cell editor when starting editing using `F2` key.
+  (issue 652)
+
+#### Fixed bugs
+
+- macOS: Setting window background (of undecorated window) to translucent color
+  (alpha < 255) did not show the window translucent. (issue #705)
+- JIDE CommandMenuBar: Fixed `ClassCastException` when JIDE command bar displays
+  `JideMenu` in popup. (PR #794)
+
+
+## 3.3
+
+#### New features and improvements
+
+- macOS (10.14+): Popups (`JPopupMenu`, `JComboBox`, `JToolTip`, etc.) now use
+  native macOS rounded borders. (PR #772; issue #715)
+- Native libraries: Added `libflatlaf-macos-arm64.dylib` and
+  `libflatlaf-macos-x86_64.dylib`. See also
+  https://www.formdev.com/flatlaf/native-libraries/.
+- ScrollPane: Support rounded border. (PR #713)
+- SplitPane: Support divider hover and pressed background colors. (PR #788)
+- TabbedPane: Support vertical tabs. (PR #758, issue #633)
+- TabbedPane: Paint rounded tab area background for rounded cards. (issue #717)
+- ToolBar: Added styling properties `separatorWidth` and `separatorColor`.
+
+#### Fixed bugs
+
+- Button and ToggleButton: Selected buttons did not use explicitly set
+  foreground color. (issue 756)
+- FileChooser: Catch NPE in Java 21 when getting icon for `.exe` files that use
+  default Windows exe icon. (see
+  [JDK-8320692](https://bugs.openjdk.org/browse/JDK-8320692))
+- OptionPane: Fixed styling custom panel background in `JOptionPane`. (issue
+  #761)
+- ScrollPane: Styling ScrollPane border properties did not work if view
+  component is a Table.
+- Table:
+  - Switching theme looses table grid and intercell spacing. (issues #733 and
+    #750)
+  - Fixed background of `boolean` columns when using alternating row colors.
+    (issue #780)
+  - Fixed border arc of components in complex table cell editors. (issue #786)
+- TableHeader:
+  - No longer temporary replace header cell renderer while painting. This avoids
+    a `StackOverflowError` in case that custom renderer does this too. (see
+    [NetBeans issue #6835](https://github.com/apache/netbeans/issues/6835)) This
+    also improves compatibility with custom table header implementations.
+  - Header cell renderer background/foreground colors were not restored after
+    hover if renderer uses `null` for background/foreground. (PR #790)
+- TabbedPane:
+  - Avoid unnecessary repainting whole tabbed pane content area when layouting
+    leading/trailing components.
+  - Avoid unnecessary repainting of selected tab on temporary changes.
+  - Fixed "endless" layouting and repainting when using nested tabbed panes (top
+    and bottom tab placement) and RSyntaxTextArea (with enabled line-wrapping)
+    as tab content. (see
+    [jadx issue #2030](https://github.com/skylot/jadx/issues/2030))
+- Fixed broken rendering after resizing window to minimum size and then
+  increasing size again. (issue #767)
+
+#### Incompatibilities
+
+- Removed support for JetBrains custom decorations, which required
+  [JetBrains Runtime](https://github.com/JetBrains/JetBrainsRuntime/wiki) (JBR)
+  8 or 11. It did not work for JBR 17. System property
+  `flatlaf.useJetBrainsCustomDecorations` is now ignored. **Note**: FlatLaf
+  window decorations continue to work with JBR.
+
+
+## 3.2.5
+
+#### Fixed bugs
+
+- Popup: Fixed NPE if popup invoker is `null` on Windows 10. (issue #753;
+  regression in 3.2.1 in fix for #626)
+
+
+## 3.2.4
+
+#### Fixed bugs
+
+- Popup: Fixed NPE if popup invoker is `null` on Linux with Wayland and Java 21.
+  (issue #752; regression in 3.2.3)
+
+
+## 3.2.3
+
+#### Fixed bugs
+
+- Popup: Popups that request focus were not shown on Linux with Wayland and Java 21.
+  (issue #752)
+
+
+## 3.2.2
+
+#### Fixed bugs
+
+- Button: Fixed painting icon and text at wrong location when using HTML text,
+  left/right vertical alignment and running in Java 19+. (issue #746)
+- CheckBox and RadioButton: Fixed cut off right side when border is removed and
+  horizontal alignment is set to `right`. (issue #734)
+- TabbedPane: Fixed NPE when using focusable component as tab component and
+  switching theme. (issue #745)
+
+
 ## 3.2.1
 
 #### Fixed bugs
@@ -16,7 +175,7 @@ FlatLaf Change Log
   #718)
 - TextField: Fixed placeholder text painting, which did not respect horizontal
   alignment property of `JTextField`. (issue #721)
-- Popop: Fixed drop shadow if popup overlaps a heavyweight component. (Windows
+- Popup: Fixed drop shadow if popup overlaps a heavyweight component. (Windows
   10 only; issue #626)
 
 
@@ -142,7 +301,6 @@ FlatLaf Change Log
   - Windows DLLs are now digitally signed with FormDev Software GmbH
     certificate.
 
-
 #### Fixed bugs
 
 - FlatLaf window decorations:

README.md

@@ -62,7 +62,7 @@ build script:
     artifactId:  flatlaf
     version:     (see button below)
 
-Otherwise download `flatlaf-<version>.jar` here:
+Otherwise, download `flatlaf-<version>.jar` here:
 
 [![Maven Central](https://maven-badges.herokuapp.com/maven-central/com.formdev/flatlaf/badge.svg?style=flat-square&color=007ec6)](https://maven-badges.herokuapp.com/maven-central/com.formdev/flatlaf)
 
@@ -141,7 +141,6 @@ details and downloads.
 Buzz
 ----
 
-- [What others say about FlatLaf on Twitter](https://twitter.com/search?f=live&q=flatlaf)
 - [FlatLaf 3.1 (and 3.0) announcement on Reddit](https://www.reddit.com/r/java/comments/12xgrsu/flatlaf_31_and_30_swing_look_and_feel/)
 - [FlatLaf 1.0 announcement on Reddit](https://www.reddit.com/r/java/comments/lsbcwe/flatlaf_10_swing_look_and_feel/)
 - [FlatLaf announcement on Reddit](https://www.reddit.com/r/java/comments/dl0hu3/flatlaf_flat_look_and_feel/)
@@ -312,6 +311,9 @@ Applications using FlatLaf
 
 - ![New](images/new.svg) ![Sponsor](images/sponsor.svg)
   [BGBlitz](https://www.bgblitz.com/) (**commercial**) - professional Backgammon
+- ![New](images/new.svg) [MCreator](https://github.com/MCreator/MCreator) - 
+  software used to make Minecraft Java Edition mods, Minecraft Bedrock Edition Add-Ons, 
+  and data packs without programming knowledge
 - ![New](images/new.svg) [MapTool](https://github.com/RPTools/maptool) - virtual
   Tabletop for playing role-playing games
 - [MegaMek](https://github.com/MegaMek/megamek),

build.gradle.kts

@@ -18,6 +18,12 @@ import net.ltgt.gradle.errorprone.errorprone
 
 version = property( if( hasProperty( "release" ) ) "flatlaf.releaseVersion" else "flatlaf.developmentVersion" ) as String
 
+// for PR snapshots change version to 'PR-<pr_number>-SNAPSHOT'
+val pullRequestNumber = findProperty( "github.event.pull_request.number" )
+if( pullRequestNumber != null )
+	version = "PR-${pullRequestNumber}-SNAPSHOT"
+
+
 allprojects {
 	version = rootProject.version
 

buildSrc/src/main/java/ReorderJarEntries.java

@@ -45,7 +45,7 @@ public class ReorderJarEntries
 			// 1st pass: copy .properties files
 			copyFiles( zipOutStream, jarFile, name -> name.endsWith( ".properties" ) );
 
-			// 2st pass: copy other files
+			// 2nd pass: copy other files
 			copyFiles( zipOutStream, jarFile, name -> !name.endsWith( ".properties" ) );
 		}
 

buildSrc/src/main/kotlin/flatlaf-cpp-library.gradle.kts

@@ -27,7 +27,7 @@ library {
 		}
 		with( linkTask.get() ) {
 			if( name.contains( "Release" ) )
-				debuggable.set( false )
+				debuggable = false
 		}
 	}
 }

buildSrc/src/main/kotlin/flatlaf-jni-headers.gradle.kts

@@ -26,7 +26,7 @@ tasks {
 		// depend on :flatlaf-core:compileJava because it generates the JNI headers
 		dependsOn( ":flatlaf-core:compileJava" )
 
-		from( project( ":flatlaf-core" ).buildDir.resolve( "generated/jni-headers" ) )
+		from( project( ":flatlaf-core" ).layout.buildDirectory.dir( "generated/jni-headers" ) )
 		into( "src/main/headers" )
 		include( extension.headers )
 		filter<org.apache.tools.ant.filters.FixCrLfFilter>(

buildSrc/src/main/kotlin/flatlaf-publish.gradle.kts

@@ -44,34 +44,34 @@ publishing {
 
 			pom {
 				afterEvaluate {
-					this@pom.name.set( extension.name )
-					this@pom.description.set( extension.description )
+					this@pom.name = extension.name
+					this@pom.description = extension.description
 				}
-				url.set( "https://github.com/JFormDesigner/FlatLaf" )
+				url = "https://github.com/JFormDesigner/FlatLaf"
 
 				licenses {
 					license {
-						name.set( "The Apache License, Version 2.0" )
-						url.set( "https://www.apache.org/licenses/LICENSE-2.0.txt" )
+						name = "The Apache License, Version 2.0"
+						url = "https://www.apache.org/licenses/LICENSE-2.0.txt"
 					}
 				}
 
 				developers {
 					developer {
-						name.set( "Karl Tauber" )
-						organization.set( "FormDev Software GmbH" )
-						organizationUrl.set( "https://www.formdev.com/" )
+						name = "Karl Tauber"
+						organization = "FormDev Software GmbH"
+						organizationUrl = "https://www.formdev.com/"
 					}
 				}
 
 				scm {
-					connection.set( "scm:git:git://github.com/JFormDesigner/FlatLaf.git" )
-					url.set( "https://github.com/JFormDesigner/FlatLaf" )
+					connection = "scm:git:git://github.com/JFormDesigner/FlatLaf.git"
+					url = "https://github.com/JFormDesigner/FlatLaf"
 				}
 
 				issueManagement {
-					system.set( "GitHub" )
-					url.set( "https://github.com/JFormDesigner/FlatLaf/issues" )
+					system = "GitHub"
+					url = "https://github.com/JFormDesigner/FlatLaf/issues"
 				}
 			}
 
@@ -124,7 +124,7 @@ tasks.withType<Sign>().configureEach {
 }
 
 // check whether parallel build is enabled
-tasks.withType<PublishToMavenRepository>().configureEach {
+tasks.withType<AbstractPublishToMaven>().configureEach {
 	doFirst {
 		if( System.getProperty( "org.gradle.parallel" ) == "true" )
 			throw RuntimeException( "Publishing does not work correctly with enabled parallel build. Disable parallel build with VM option '-Dorg.gradle.parallel=false'." )

buildSrc/src/main/kotlin/flatlaf-toolchain.gradle.kts

@@ -21,6 +21,6 @@ plugins {
 val toolchainJavaVersion = System.getProperty( "toolchain" )
 if( !toolchainJavaVersion.isNullOrEmpty() ) {
 	java.toolchain {
-		languageVersion.set( JavaLanguageVersion.of( toolchainJavaVersion ) )
+		languageVersion = JavaLanguageVersion.of( toolchainJavaVersion )
 	}
 }

flatlaf-core/build.gradle.kts

@@ -27,8 +27,8 @@ plugins {
 val sigtest = configurations.create( "sigtest" )
 
 dependencies {
-	testImplementation( libs.bundles.junit )
-	testRuntimeOnly( libs.junit.engine )
+	testImplementation( libs.junit )
+	testRuntimeOnly( libs.junit.launcher )
 
 	// https://github.com/jtulach/netbeans-apitest
 	sigtest( libs.sigtest )
@@ -42,11 +42,11 @@ java {
 tasks {
 	compileJava {
 		// generate JNI headers
-		options.headerOutputDirectory.set( buildDir.resolve( "generated/jni-headers" ) )
+		options.headerOutputDirectory = layout.buildDirectory.dir( "generated/jni-headers" )
 	}
 
 	jar {
-		archiveBaseName.set( "flatlaf" )
+		archiveBaseName = "flatlaf"
 
 		doLast {
 			ReorderJarEntries.reorderJarEntries( outputs.files.singleFile );
@@ -54,11 +54,32 @@ tasks {
 	}
 
 	named<Jar>( "sourcesJar" ) {
-		archiveBaseName.set( "flatlaf" )
+		archiveBaseName = "flatlaf"
 	}
 
 	named<Jar>( "javadocJar" ) {
-		archiveBaseName.set( "flatlaf" )
+		archiveBaseName = "flatlaf"
+	}
+
+	register<Zip>( "jarNoNatives" ) {
+		group = "build"
+		dependsOn( "jar" )
+
+		archiveBaseName = "flatlaf"
+		archiveClassifier = "no-natives"
+		archiveExtension = "jar"
+		destinationDirectory = layout.buildDirectory.dir( "libs" )
+
+		from( zipTree( jar.get().archiveFile.get().asFile ) )
+		exclude( "com/formdev/flatlaf/natives/**" )
+	}
+
+	withType<AbstractPublishToMaven>().configureEach {
+		dependsOn( "jarNoNatives" )
+	}
+
+	withType<Sign>().configureEach {
+		dependsOn( "jarNoNatives" )
 	}
 
 	check {
@@ -127,9 +148,13 @@ flatlafPublish {
 
 	val natives = "src/main/resources/com/formdev/flatlaf/natives"
 	nativeArtifacts = listOf(
+		NativeArtifact( tasks.getByName( "jarNoNatives" ).outputs.files.asPath, "no-natives", "jar" ),
+
 		NativeArtifact( "${natives}/flatlaf-windows-x86.dll",       "windows-x86",    "dll" ),
 		NativeArtifact( "${natives}/flatlaf-windows-x86_64.dll",    "windows-x86_64", "dll" ),
 		NativeArtifact( "${natives}/flatlaf-windows-arm64.dll",     "windows-arm64",  "dll" ),
+		NativeArtifact( "${natives}/libflatlaf-macos-arm64.dylib",  "macos-arm64",    "dylib" ),
+		NativeArtifact( "${natives}/libflatlaf-macos-x86_64.dylib", "macos-x86_64",   "dylib" ),
 		NativeArtifact( "${natives}/libflatlaf-linux-x86_64.so",    "linux-x86_64",   "so" ),
 	)
 }

flatlaf-core/flatlaf-core-sigtest.txt

@@ -1,5 +1,5 @@
 #Signature file v4.1
-#Version 3.2.1
+#Version 3.4
 
 CLSS public abstract interface com.formdev.flatlaf.FlatClientProperties
 fld public final static java.lang.String BUTTON_TYPE = "JButton.buttonType"
@@ -12,7 +12,13 @@ fld public final static java.lang.String BUTTON_TYPE_TOOLBAR_BUTTON = "toolBarBu
 fld public final static java.lang.String COMPONENT_FOCUS_OWNER = "JComponent.focusOwner"
 fld public final static java.lang.String COMPONENT_ROUND_RECT = "JComponent.roundRect"
 fld public final static java.lang.String COMPONENT_TITLE_BAR_CAPTION = "JComponent.titleBarCaption"
+fld public final static java.lang.String FULL_WINDOW_CONTENT = "FlatLaf.fullWindowContent"
+fld public final static java.lang.String FULL_WINDOW_CONTENT_BUTTONS_BOUNDS = "FlatLaf.fullWindowContent.buttonsBounds"
+fld public final static java.lang.String FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER = "FlatLaf.fullWindowContent.buttonsPlaceholder"
 fld public final static java.lang.String GLASS_PANE_FULL_HEIGHT = "JRootPane.glassPaneFullHeight"
+fld public final static java.lang.String MACOS_WINDOW_BUTTONS_SPACING = "FlatLaf.macOS.windowButtonsSpacing"
+fld public final static java.lang.String MACOS_WINDOW_BUTTONS_SPACING_LARGE = "large"
+fld public final static java.lang.String MACOS_WINDOW_BUTTONS_SPACING_MEDIUM = "medium"
 fld public final static java.lang.String MENU_BAR_EMBEDDED = "JRootPane.menuBarEmbedded"
 fld public final static java.lang.String MINIMUM_HEIGHT = "JComponent.minimumHeight"
 fld public final static java.lang.String MINIMUM_WIDTH = "JComponent.minimumWidth"
@@ -23,6 +29,7 @@ fld public final static java.lang.String PLACEHOLDER_TEXT = "JTextField.placehol
 fld public final static java.lang.String POPUP_BORDER_CORNER_RADIUS = "Popup.borderCornerRadius"
 fld public final static java.lang.String POPUP_DROP_SHADOW_PAINTED = "Popup.dropShadowPainted"
 fld public final static java.lang.String POPUP_FORCE_HEAVY_WEIGHT = "Popup.forceHeavyWeight"
+fld public final static java.lang.String POPUP_ROUNDED_BORDER_WIDTH = "Popup.roundedBorderWidth"
 fld public final static java.lang.String PROGRESS_BAR_LARGE_HEIGHT = "JProgressBar.largeHeight"
 fld public final static java.lang.String PROGRESS_BAR_SQUARE = "JProgressBar.square"
 fld public final static java.lang.String SCROLL_BAR_SHOW_BUTTONS = "JScrollBar.showButtons"
@@ -67,6 +74,11 @@ fld public final static java.lang.String TABBED_PANE_TAB_CLOSE_TOOLTIPTEXT = "JT
 fld public final static java.lang.String TABBED_PANE_TAB_HEIGHT = "JTabbedPane.tabHeight"
 fld public final static java.lang.String TABBED_PANE_TAB_ICON_PLACEMENT = "JTabbedPane.tabIconPlacement"
 fld public final static java.lang.String TABBED_PANE_TAB_INSETS = "JTabbedPane.tabInsets"
+fld public final static java.lang.String TABBED_PANE_TAB_ROTATION = "JTabbedPane.tabRotation"
+fld public final static java.lang.String TABBED_PANE_TAB_ROTATION_AUTO = "auto"
+fld public final static java.lang.String TABBED_PANE_TAB_ROTATION_LEFT = "left"
+fld public final static java.lang.String TABBED_PANE_TAB_ROTATION_NONE = "none"
+fld public final static java.lang.String TABBED_PANE_TAB_ROTATION_RIGHT = "right"
 fld public final static java.lang.String TABBED_PANE_TAB_TYPE = "JTabbedPane.tabType"
 fld public final static java.lang.String TABBED_PANE_TAB_TYPE_CARD = "card"
 fld public final static java.lang.String TABBED_PANE_TAB_TYPE_UNDERLINED = "underlined"
@@ -241,7 +253,7 @@ meth public void setExtraDefaults(java.util.Map<java.lang.String,java.lang.Strin
 meth public void uninitialize()
 meth public void unregisterUIDefaultsGetter(java.util.function.Function<java.lang.Object,java.lang.Object>)
 supr javax.swing.plaf.basic.BasicLookAndFeel
-hfds DESKTOPFONTHINTS,aquaLoaded,customDefaultsSources,desktopPropertyListener,desktopPropertyName,desktopPropertyName2,extraDefaults,getUIMethod,getUIMethodInitialized,globalExtraDefaults,mnemonicHandler,oldPopupFactory,postInitialization,preferredFontFamily,preferredLightFontFamily,preferredMonospacedFontFamily,preferredSemiboldFontFamily,subMenuUsabilityHelperInstalled,systemColorGetter,uiDefaultsGetters,updateUIPending
+hfds DESKTOPFONTHINTS,aquaLoaded,customDefaultsSources,desktopPropertyListener,desktopPropertyName,desktopPropertyName2,extraDefaults,globalExtraDefaults,mnemonicHandler,oldPopupFactory,postInitialization,preferredFontFamily,preferredLightFontFamily,preferredMonospacedFontFamily,preferredSemiboldFontFamily,subMenuUsabilityHelperInstalled,systemColorGetter,uiDefaultsGetters,updateUIPending
 hcls ActiveFont,FlatUIDefaults,ImageIconUIResource
 
 CLSS public abstract interface static com.formdev.flatlaf.FlatLaf$DisabledIconProvider
@@ -282,6 +294,7 @@ fld public final static java.lang.String UI_SCALE_ALLOW_SCALE_DOWN = "flatlaf.ui
 fld public final static java.lang.String UI_SCALE_ENABLED = "flatlaf.uiScale.enabled"
 fld public final static java.lang.String UPDATE_UI_ON_SYSTEM_FONT_CHANGE = "flatlaf.updateUIOnSystemFontChange"
 fld public final static java.lang.String USE_JETBRAINS_CUSTOM_DECORATIONS = "flatlaf.useJetBrainsCustomDecorations"
+ anno 0 java.lang.Deprecated()
 fld public final static java.lang.String USE_NATIVE_LIBRARY = "flatlaf.useNativeLibrary"
 fld public final static java.lang.String USE_TEXT_Y_CORRECTION = "flatlaf.useTextYCorrection"
 fld public final static java.lang.String USE_UBUNTU_FONT = "flatlaf.useUbuntuFont"

flatlaf-core/src/main/java/com/formdev/flatlaf/FlatClientProperties.java

@@ -33,7 +33,7 @@ public interface FlatClientProperties
 	//---- JButton ------------------------------------------------------------
 
 	/**
-	 * Specifies type of a button.
+	 * Specifies type of button.
 	 * <p>
 	 * <strong>Components</strong> {@link javax.swing.JButton} and {@link javax.swing.JToggleButton}<br>
 	 * <strong>Value type</strong> {@link java.lang.String}<br>
@@ -102,6 +102,17 @@ public interface FlatClientProperties
 	 */
 	String BUTTON_TYPE_BORDERLESS = "borderless";
 
+	/**
+	 * Specifies whether the button preferred size will be made square (quadratically).
+	 * <p>
+	 * <strong>Components</strong> {@link javax.swing.JButton} and {@link javax.swing.JToggleButton}<br>
+	 * <strong>Value type</strong> {@link java.lang.Boolean}
+	 */
+	String SQUARE_SIZE = "JButton.squareSize";
+
+
+	//---- JCheckBox ----------------------------------------------------------
+
 	/**
 	 * Specifies selected state of a checkbox.
 	 * <p>
@@ -118,14 +129,6 @@ public interface FlatClientProperties
 	 */
 	String SELECTED_STATE_INDETERMINATE = "indeterminate";
 
-	/**
-	 * Specifies whether the button preferred size will be made square (quadratically).
-	 * <p>
-	 * <strong>Components</strong> {@link javax.swing.JButton} and {@link javax.swing.JToggleButton}<br>
-	 * <strong>Value type</strong> {@link java.lang.Boolean}
-	 */
-	String SQUARE_SIZE = "JButton.squareSize";
-
 
 	//---- JComponent ---------------------------------------------------------
 
@@ -257,19 +260,116 @@ public interface FlatClientProperties
 	String COMPONENT_FOCUS_OWNER = "JComponent.focusOwner";
 
 	/**
-	 * Specifies whether a component in an embedded menu bar should behave as caption
+	 * Specifies whether a component shown in a window title bar area should behave as caption
 	 * (left-click allows moving window, right-click shows window system menu).
-	 * The component does not receive mouse pressed/released/clicked/dragged events,
+	 * The caption component does not receive mouse pressed/released/clicked/dragged events,
 	 * but it gets mouse entered/exited/moved events.
 	 * <p>
+	 * Since 3.4, this client property also supports using a function that can check
+	 * whether a given location in the component should behave as caption.
+	 * Useful for components that do not use mouse input on whole component bounds.
+	 *
+	 * <pre>{@code
+	 * myComponent.putClientProperty( "JComponent.titleBarCaption",
+	 *     (Function<Point, Boolean>) pt -> {
+	 *         // parameter pt contains mouse location (in myComponent coordinates)
+	 *         // return true if the component is not interested in mouse input at the given location
+	 *         // return false if the component wants process mouse input at the given location
+	 *         // return null if the component children should be checked
+	 *         return ...; // check here
+	 *     } );
+	 * }</pre>
+	 * <b>Warning</b>:
+	 * <ul>
+	 *   <li>This function is invoked often when mouse is moved over window title bar area
+	 *       and should therefore return quickly.
+	 *   <li>This function is invoked on 'AWT-Windows' thread (not 'AWT-EventQueue' thread)
+	 *       while processing Windows messages.
+	 *       It <b>must not</b> change any component property or layout because this could cause a dead lock.
+	 * </ul>
+	 * <p>
 	 * <strong>Component</strong> {@link javax.swing.JComponent}<br>
-	 * <strong>Value type</strong> {@link java.lang.Boolean}
+	 * <strong>Value type</strong> {@link java.lang.Boolean} or {@link java.util.function.Function}&lt;Point, Boolean&gt;
 	 *
 	 * @since 2.5
 	 */
 	String COMPONENT_TITLE_BAR_CAPTION = "JComponent.titleBarCaption";
 
 
+	//---- Panel --------------------------------------------------------------
+
+	/**
+	 * Marks the panel as placeholder for the iconfify/maximize/close buttons
+	 * in fullWindowContent mode. See {@link #FULL_WINDOW_CONTENT}.
+	 * <p>
+	 * If fullWindowContent mode is enabled, the preferred size of the panel is equal
+	 * to the size of the iconfify/maximize/close buttons. Otherwise is is {@code 0,0}.
+	 * <p>
+	 * You're responsible to layout that panel at the top-left or top-right corner,
+	 * depending on platform, where the iconfify/maximize/close buttons are located.
+	 * <p>
+	 * Syntax of the value string is: {@code "win|mac [horizontal|vertical] [zeroInFullScreen] [leftToRight|rightToLeft]"}.
+	 * <p>
+	 * The string must start with {@code "win"} (for Windows or Linux) or
+	 * with {@code "mac"} (for macOS) and specifies the platform where the placeholder
+	 * should be used. On macOS, you need the placeholder in the top-left corner,
+	 * but on Windows/Linux you need it in the top-right corner. So if your application supports
+	 * fullWindowContent mode on both platforms, you can add two placeholders to your layout
+	 * and FlatLaf automatically uses only one of them. The other gets size {@code 0,0}.
+	 * <p>
+	 * Optionally, you can append following options to the value string (separated by space characters):
+	 * <ul>
+	 *   <li>{@code "horizontal"} - preferred height is zero
+	 *   <li>{@code "vertical"} - preferred width is zero
+	 *   <li>{@code "zeroInFullScreen"} - in full-screen mode on macOS, preferred size is {@code 0,0}
+	 *   <li>{@code "leftToRight"} - in right-to-left component orientation, preferred size is {@code 0,0}
+	 *   <li>{@code "rightToLeft"} - in left-to-right component orientation, preferred size is {@code 0,0}
+	 * </ul>
+	 *
+	 * Example for adding placeholder to top-left corner on macOS:
+	 * <pre>{@code
+	 * JPanel placeholder = new JPanel();
+	 * placeholder.putClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER, "mac" );
+     *
+     * JToolBar toolBar = new JToolBar();
+     * // add tool bar items
+     *
+	 * JPanel toolBarPanel = new JPanel( new BorderLayout() );
+	 * toolBarPanel.add( placeholder, BorderLayout.WEST );
+	 * toolBarPanel.add( toolBar, BorderLayout.CENTER );
+	 *
+	 * frame.getContentPane().add( toolBarPanel, BorderLayout.NORTH );
+	 * }</pre>
+	 *
+	 * Or add placeholder as first item to the tool bar:
+	 * <pre>{@code
+	 * JPanel placeholder = new JPanel();
+	 * placeholder.putClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER, "mac" );
+	 *
+	 * JToolBar toolBar = new JToolBar();
+	 * toolBar.add( placeholder );
+	 * // add tool bar items
+	 *
+	 * frame.getContentPane().add( toolBar, BorderLayout.NORTH );
+	 * }</pre>
+	 *
+	 * If a tabbed pane is located at the top, you can add the placeholder
+	 * as leading component to that tabbed pane:
+	 * <pre>{@code
+	 * JPanel placeholder = new JPanel();
+	 * placeholder.putClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER, "mac" );
+	 *
+	 * tabbedPane.putClientProperty( FlatClientProperties.TABBED_PANE_LEADING_COMPONENT, placeholder );
+	 * }</pre>
+	 * <p>
+	 * <strong>Component</strong> {@link javax.swing.JPanel}<br>
+	 * <strong>Value type</strong> {@link java.lang.String}
+	 *
+	 * @since 3.4
+	 */
+	String FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER = "FlatLaf.fullWindowContent.buttonsPlaceholder";
+
+
 	//---- Popup --------------------------------------------------------------
 
 	/**
@@ -278,12 +378,13 @@ public interface FlatClientProperties
 	 * <p>
 	 * Note that this is not available on all platforms since it requires special support.
 	 * Supported platforms:
-	 * <p>
-	 * <strong>Windows 11</strong> (x86 or x86_64): Only two corner radiuses are supported
+	 * <ul>
+	 * <li><strong>Windows 11</strong>: Only two corner radiuses are supported
 	 *     by the OS: {@code DWMWCP_ROUND} is 8px and {@code DWMWCP_ROUNDSMALL} is 4px.
 	 *     If this value is {@code 1 - 4}, then {@code DWMWCP_ROUNDSMALL} is used.
 	 *     If it is {@code >= 5}, then {@code DWMWCP_ROUND} is used.
-	 * <p>
+	 * <li><strong>macOS</strong> (10.14 and later): Any corner radius is supported.
+	 * </ul>
 	 * <strong>Component</strong> {@link javax.swing.JComponent}<br>
 	 * <strong>Value type</strong> {@link java.lang.Integer}<br>
 	 *
@@ -291,6 +392,24 @@ public interface FlatClientProperties
 	 */
 	String POPUP_BORDER_CORNER_RADIUS = "Popup.borderCornerRadius";
 
+	/**
+	 * Specifies the popup rounded border width if the component is shown in a popup
+	 * or if the component is the owner of another component that is shown in a popup.
+	 * <p>
+	 * Only used if popup uses rounded border.
+	 * <p>
+	 * Note that this is not available on all platforms since it requires special support.
+	 * Supported platforms:
+	 * <ul>
+	 * <li><strong>macOS</strong> (10.14 and later)
+	 * </ul>
+	 * <strong>Component</strong> {@link javax.swing.JComponent}<br>
+	 * <strong>Value type</strong> {@link java.lang.Integer} or {@link java.lang.Float}<br>
+	 *
+	 * @since 3.3
+	 */
+	String POPUP_ROUNDED_BORDER_WIDTH = "Popup.roundedBorderWidth";
+
 	/**
 	 * Specifies whether a drop shadow is painted if the component is shown in a popup
 	 * or if the component is the owner of another component that is shown in a popup.
@@ -369,6 +488,46 @@ public interface FlatClientProperties
 	 */
 	String MENU_BAR_EMBEDDED = "JRootPane.menuBarEmbedded";
 
+	/**
+	 * Specifies whether the content pane (and the glass pane) should be extended
+	 * into the window title bar area
+	 * (requires enabled window decorations). Default is {@code false}.
+	 * <p>
+	 * On macOS, use client property {@code apple.awt.fullWindowContent}
+	 * (see <a href="https://www.formdev.com/flatlaf/macos/#full_window_content">macOS Full window content</a>).
+	 * <p>
+	 * Setting this enables/disables full window content
+	 * for the {@code JFrame} or {@code JDialog} that contains the root pane.
+	 * <p>
+	 * If {@code true}, the content pane (and the glass pane) is extended into
+	 * the title bar area. The window icon and title are hidden.
+	 * Only the iconfify/maximize/close buttons stay visible in the upper right corner
+	 * (and overlap the content pane).
+	 * <p>
+	 * The user can left-click-and-drag on the title bar area to move the window,
+	 * except when clicking on a component that processes mouse events (e.g. buttons or menus).
+	 * <p>
+	 * <strong>Component</strong> {@link javax.swing.JRootPane}<br>
+	 * <strong>Value type</strong> {@link java.lang.Boolean}
+	 *
+	 * @since 3.4
+	 */
+	String FULL_WINDOW_CONTENT = "FlatLaf.fullWindowContent";
+
+	/**
+	 * Contains the current bounds of the iconfify/maximize/close buttons
+	 * (in root pane coordinates) if fullWindowContent mode is enabled.
+	 * Otherwise its value is {@code null}.
+	 * <p>
+	 * <b>Note</b>: Do not set this client property. It is set by FlatLaf.
+	 * <p>
+	 * <strong>Component</strong> {@link javax.swing.JRootPane}<br>
+	 * <strong>Value type</strong> {@link java.awt.Rectangle}
+	 *
+	 * @since 3.4
+	 */
+	String FULL_WINDOW_CONTENT_BUTTONS_BOUNDS = "FlatLaf.fullWindowContent.buttonsBounds";
+
 	/**
 	 * Specifies whether the window icon should be shown in the window title bar
 	 * (requires enabled window decorations). Default is UI property {@code TitlePane.showIcon}.
@@ -402,10 +561,10 @@ public interface FlatClientProperties
 	String TITLE_BAR_SHOW_TITLE = "JRootPane.titleBarShowTitle";
 
 	/**
-	 * Specifies whether the "iconfify" button should be shown in the window title bar
+	 * Specifies whether the "iconify" button should be shown in the window title bar
 	 * (requires enabled window decorations). Default is {@code true}.
 	 * <p>
-	 * Setting this shows/hides the "iconfify" button
+	 * Setting this shows/hides the "iconify" button
 	 * for the {@code JFrame} that contains the root pane.
 	 * <p>
 	 * <strong>Component</strong> {@link javax.swing.JRootPane}<br>
@@ -487,7 +646,7 @@ public interface FlatClientProperties
 	 * On macOS, Java supports this out of the box.
 	 * <p>
 	 * Note that this client property must be set before the window becomes displayable.
-	 * Otherwise an {@link IllegalComponentStateException} is thrown.
+	 * Otherwise, an {@link IllegalComponentStateException} is thrown.
 	 * <p>
 	 * <strong>Component</strong> {@link javax.swing.JRootPane}<br>
 	 * <strong>Value type</strong> {@link java.lang.String}<br>
@@ -828,7 +987,7 @@ public interface FlatClientProperties
 	 * <strong>Component</strong> {@link javax.swing.JTabbedPane}<br>
 	 * <strong>Value type</strong> {@link java.lang.Integer} or {@link java.lang.String}<br>
 	 * <strong>Allowed Values</strong>
-	 *     {@link SwingConstants#LEADING} (default)
+	 *     {@link SwingConstants#LEADING} (default),
 	 *     {@link SwingConstants#TRAILING},
 	 *     {@link SwingConstants#CENTER},
 	 *     {@link #TABBED_PANE_ALIGN_LEADING} (default),
@@ -932,6 +1091,59 @@ public interface FlatClientProperties
 	 */
 	String TABBED_PANE_TAB_ICON_PLACEMENT = "JTabbedPane.tabIconPlacement";
 
+	/**
+	 * Specifies the rotation of the tabs (title, icon, etc.).
+	 * <p>
+	 * <strong>Component</strong> {@link javax.swing.JTabbedPane}<br>
+	 * <strong>Value type</strong> {@link java.lang.Integer} or {@link java.lang.String}<br>
+	 * <strong>Allowed Values</strong>
+	 *     {@link SwingConstants#LEFT},
+	 *     {@link SwingConstants#RIGHT},
+	 *     {@link #TABBED_PANE_TAB_ROTATION_NONE} (default),
+	 *     {@link #TABBED_PANE_TAB_ROTATION_AUTO},
+	 *     {@link #TABBED_PANE_TAB_ROTATION_LEFT} or
+	 *     {@link #TABBED_PANE_TAB_ROTATION_RIGHT}
+	 *
+	 * @since 3.3
+	 */
+	String TABBED_PANE_TAB_ROTATION = "JTabbedPane.tabRotation";
+
+	/**
+	 * Tabs are not rotated.
+	 *
+	 * @see #TABBED_PANE_TAB_ROTATION
+	 * @since 3.3
+	 */
+	String TABBED_PANE_TAB_ROTATION_NONE = "none";
+
+	/**
+	 * Tabs are rotated depending on tab placement.
+	 * <p>
+	 * For top and bottom tab placement, the tabs are not rotated.<br>
+	 * For left tab placement, the tabs are rotated counter-clockwise.<br>
+	 * For right tab placement, the tabs are rotated clockwise.
+	 *
+	 * @see #TABBED_PANE_TAB_ROTATION
+	 * @since 3.3
+	 */
+	String TABBED_PANE_TAB_ROTATION_AUTO = "auto";
+
+	/**
+	 * Tabs are rotated counter-clockwise.
+	 *
+	 * @see #TABBED_PANE_TAB_ROTATION
+	 * @since 3.3
+	 */
+	String TABBED_PANE_TAB_ROTATION_LEFT = "left";
+
+	/**
+	 * Tabs are rotated clockwise.
+	 *
+	 * @see #TABBED_PANE_TAB_ROTATION
+	 * @since 3.3
+	 */
+	String TABBED_PANE_TAB_ROTATION_RIGHT = "right";
+
 	/**
 	 * Specifies a component that will be placed at the leading edge of the tabs area.
 	 * <p>
@@ -1136,8 +1348,8 @@ public interface FlatClientProperties
 	 * <p>
 	 * <strong>Component</strong> {@link javax.swing.JToggleButton}<br>
 	 * <strong>Value type</strong> {@link java.lang.Integer}<br>
-	 * <strong>SupportedValues:</strong>
-	 *     {@link SwingConstants#BOTTOM} (default)
+	 * <strong>Allowed Values</strong>
+	 *     {@link SwingConstants#BOTTOM} (default),
 	 *     {@link SwingConstants#TOP},
 	 *     {@link SwingConstants#LEFT} or
 	 *     {@link SwingConstants#RIGHT}
@@ -1191,6 +1403,44 @@ public interface FlatClientProperties
 	String TREE_PAINT_SELECTION = "JTree.paintSelection";
 
 
+	//---- macOS --------------------------------------------------------------
+
+	/**
+	 * Specifies the spacing around the macOS window close/minimize/zoom buttons.
+	 * Useful if <a href="https://www.formdev.com/flatlaf/macos/#full_window_content">full window content</a>
+	 * is enabled.
+	 * <p>
+	 * (requires macOS 10.14+ for "medium" spacing and macOS 11+ for "large" spacing, requires Java 17+)
+	 * <p>
+	 * <strong>Component</strong> {@link javax.swing.JRootPane}<br>
+	 * <strong>Value type</strong> {@link java.lang.String}<br>
+	 * <strong>Allowed Values</strong>
+	 *     {@link #MACOS_WINDOW_BUTTONS_SPACING_MEDIUM} or
+	 *     {@link #MACOS_WINDOW_BUTTONS_SPACING_LARGE} (requires macOS 11+)
+	 *
+	 * @since 3.4
+	 */
+	String MACOS_WINDOW_BUTTONS_SPACING = "FlatLaf.macOS.windowButtonsSpacing";
+
+	/**
+	 * Add medium spacing around the macOS window close/minimize/zoom buttons.
+	 *
+	 * @see #MACOS_WINDOW_BUTTONS_SPACING
+	 * @since 3.4
+	 */
+	String MACOS_WINDOW_BUTTONS_SPACING_MEDIUM = "medium";
+
+	/**
+	 * Add large spacing around the macOS window close/minimize/zoom buttons.
+	 * <p>
+	 * (requires macOS 11+; "medium" is used on older systems)
+	 *
+	 * @see #MACOS_WINDOW_BUTTONS_SPACING
+	 * @since 3.4
+	 */
+	String MACOS_WINDOW_BUTTONS_SPACING_LARGE = "large";
+
+
 	//---- helper methods -----------------------------------------------------
 
 	/**

flatlaf-core/src/main/java/com/formdev/flatlaf/FlatDefaultsAddon.java

@@ -48,7 +48,7 @@ public abstract class FlatDefaultsAddon
 	public InputStream getDefaults( Class<?> lafClass ) {
 		Class<?> addonClass = this.getClass();
 		String propertiesName = '/' + addonClass.getPackage().getName().replace( '.', '/' )
-			+ '/' + lafClass.getSimpleName() + ".properties";
+			+ '/' + UIDefaultsLoader.simpleClassName( lafClass ) + ".properties";
 		return addonClass.getResourceAsStream( propertiesName );
 	}
 

flatlaf-core/src/main/java/com/formdev/flatlaf/FlatInputMaps.java

@@ -71,7 +71,7 @@ class FlatInputMaps
 			);
 		}
 
-		// join ltr and rtl bindings to fix up/down/etc keys in right-to-left component orientation
+		// join ltr and rtl bindings to fix up/down/etc. keys in right-to-left component orientation
 		Object[] bindings = (Object[]) defaults.get( "PopupMenu.selectedWindowInputMapBindings" );
 		Object[] rtlBindings = (Object[]) defaults.get( "PopupMenu.selectedWindowInputMapBindings.RightToLeft" );
 		if( bindings != null && rtlBindings != null ) {

flatlaf-core/src/main/java/com/formdev/flatlaf/FlatLaf.java

@@ -30,9 +30,6 @@ import java.awt.image.ImageProducer;
 import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
 import java.io.File;
-import java.lang.invoke.MethodHandle;
-import java.lang.invoke.MethodHandles;
-import java.lang.invoke.MethodType;
 import java.lang.reflect.Method;
 import java.net.URL;
 import java.util.ArrayList;
@@ -78,6 +75,7 @@ import com.formdev.flatlaf.ui.FlatNativeWindowBorder;
 import com.formdev.flatlaf.ui.FlatPopupFactory;
 import com.formdev.flatlaf.ui.FlatRootPaneUI;
 import com.formdev.flatlaf.ui.FlatUIUtils;
+import com.formdev.flatlaf.ui.JavaCompatibility2;
 import com.formdev.flatlaf.ui.FlatStylingSupport.StyleableUI;
 import com.formdev.flatlaf.util.FontUtils;
 import com.formdev.flatlaf.util.GrayFilter;
@@ -183,17 +181,11 @@ public abstract class FlatLaf
 	 * This depends on the operating system and on the used Java runtime.
 	 * <p>
 	 * This method returns {@code true} on Windows 10/11 (see exception below)
-	 * and on Linux, {@code false} otherwise.
+	 * and on Linux, otherwise returns {@code false}.
+	 * <p>
+	 * Returns also {@code false} on Windows 10/11 if
+	 * FlatLaf native window border support is available (requires Windows 10/11).
 	 * <p>
-	 * Returns also {@code false} on Windows 10/11 if:
-	 * <ul>
-	 * <li>FlatLaf native window border support is available (requires Windows 10/11)</li>
-	 * <li>running in
-	 * <a href="https://confluence.jetbrains.com/display/JBR/JetBrains+Runtime">JetBrains Runtime 11 (or later)</a>
-	 * (<a href="https://github.com/JetBrains/JetBrainsRuntime">source code on github</a>)
-	 * and JBR supports custom window decorations
-	 * </li>
-	 * </ul>
 	 * In these cases, custom decorations are enabled by the root pane.
 	 * Usage of {@link JFrame#setDefaultLookAndFeelDecorated(boolean)} or
 	 * {@link JDialog#setDefaultLookAndFeelDecorated(boolean)} is not necessary.
@@ -1295,8 +1287,8 @@ public abstract class FlatLaf
 	 * @since 2.5
 	 */
 	public static Map<String, Class<?>> getStyleableInfos( JComponent c ) {
-		StyleableUI ui = getStyleableUI( c );
-		return (ui != null) ? ui.getStyleableInfos( c ) : null;
+		ComponentUI ui = JavaCompatibility2.getUI( c );
+		return (ui instanceof StyleableUI) ? ((StyleableUI)ui).getStyleableInfos( c ) : null;
 	}
 
 	/**
@@ -1308,41 +1300,10 @@ public abstract class FlatLaf
 	 */
 	@SuppressWarnings( "unchecked" )
 	public static <T> T getStyleableValue( JComponent c, String key ) {
-		StyleableUI ui = getStyleableUI( c );
-		return (ui != null) ? (T) ui.getStyleableValue( c, key ) : null;
+		ComponentUI ui = JavaCompatibility2.getUI( c );
+		return (ui instanceof StyleableUI) ? (T) ((StyleableUI)ui).getStyleableValue( c, key ) : null;
 	}
 
-	private static StyleableUI getStyleableUI( JComponent c ) {
-		if( !getUIMethodInitialized ) {
-			getUIMethodInitialized = true;
-
-			if( SystemInfo.isJava_9_orLater ) {
-				try {
-					// JComponent.getUI() is available since Java 9
-					getUIMethod = MethodHandles.lookup().findVirtual( JComponent.class, "getUI",
-						MethodType.methodType( ComponentUI.class ) );
-				} catch( Exception ex ) {
-					// ignore
-				}
-			}
-		}
-
-		try {
-			Object ui;
-			if( getUIMethod != null )
-				ui = getUIMethod.invoke( c );
-			else
-				ui = c.getClass().getMethod( "getUI" ).invoke( c );
-			return (ui instanceof StyleableUI) ? (StyleableUI) ui : null;
-		} catch( Throwable ex ) {
-			// ignore
-			return null;
-		}
-	}
-
-	private static boolean getUIMethodInitialized;
-	private static MethodHandle getUIMethod;
-
 	/**
 	 * Returns the preferred font family to be used for (nearly) all fonts; or {@code null}.
 	 *

flatlaf-core/src/main/java/com/formdev/flatlaf/FlatSystemProperties.java

@@ -103,7 +103,10 @@ public interface FlatSystemProperties
 	 * <p>
 	 * <strong>Allowed Values</strong> {@code false} and {@code true}<br>
 	 * <strong>Default</strong> {@code false} (since v2; was {@code true} in v1)
+	 *
+	 * @deprecated No longer used since FlatLaf 3.3. Retained for API compatibility.
 	 */
+	@Deprecated
 	String USE_JETBRAINS_CUSTOM_DECORATIONS = "flatlaf.useJetBrainsCustomDecorations";
 
 	/**
@@ -169,19 +172,33 @@ public interface FlatSystemProperties
 	String USE_NATIVE_LIBRARY = "flatlaf.useNativeLibrary";
 
 	/**
-	 * Specifies a directory in which the native FlatLaf libraries have been extracted.
+	 * Specifies a directory in which the FlatLaf native libraries are searched for.
 	 * The path can be absolute or relative to current application working directory.
 	 * This can be used to avoid extraction of the native libraries to the temporary directory at runtime.
 	 * <p>
-	 * If the value is {@code "system"}, then {@link System#loadLibrary(String)} is
-	 * used to load the native library.
-	 * Searches for the native library in classloader of caller
+	 * If the value is {@code "system"} (supported since FlatLaf 2.6),
+	 * then {@link System#loadLibrary(String)} is used to load the native library.
+	 * This searches for the native library in classloader of caller
 	 * (using {@link ClassLoader#findLibrary(String)}) and in paths specified
 	 * in system properties {@code sun.boot.library.path} and {@code java.library.path}.
-	 * (supported since FlatLaf 2.6)
 	 * <p>
-	 * If the native library can not loaded from the given path (or via {@link System#loadLibrary(String)}),
+	 * If the native library can not be loaded from the given path (or via {@link System#loadLibrary(String)}),
 	 * then the embedded native library is extracted to the temporary directory and loaded from there.
+	 * <p>
+	 * The file names of the native libraries must be either:
+	 * <ul>
+	 *   <li>the same as in flatlaf.jar in package 'com/formdev/flatlaf/natives' (required for "system") or
+	 *   <li>when downloaded from Maven central then as described here:
+	 *     <a href="https://www.formdev.com/flatlaf/native-libraries/">https://www.formdev.com/flatlaf/native-libraries/</a>
+	 *     (requires FlatLaf 3.4)
+	 * </ul>
+	 * <p>
+	 * <strong>Note</strong>: Since FlatLaf 3.1 it is recommended to download the
+	 * FlatLaf native libraries from Maven central and distribute them with your
+	 * application in the same directory as flatlaf.jar.
+	 * Then it is <strong>not necessary</strong> to set this system property.
+	 * See <a href="https://www.formdev.com/flatlaf/native-libraries/">https://www.formdev.com/flatlaf/native-libraries/</a>
+	 * for details.
 	 *
 	 * @since 2
 	 */

flatlaf-core/src/main/java/com/formdev/flatlaf/LinuxFontPolicy.java

@@ -203,7 +203,7 @@ class LinuxFontPolicy
 	 * Gets the default font for KDE from KDE configuration files.
 	 *
 	 * The Swing fonts are not updated when the user changes system font size
-	 * (System Settings > Fonts > Force Font DPI). A application restart is necessary.
+	 * (System Settings > Fonts > Force Font DPI). An application restart is necessary.
 	 * This is the same behavior as in native KDE applications.
 	 *
 	 * The "display scale factor" (kdeglobals: [KScreen] > ScaleFactor) is not used

flatlaf-core/src/main/java/com/formdev/flatlaf/SubMenuUsabilityHelper.java

@@ -172,7 +172,7 @@ debug*/
 		targetTopY = popupLocation.y;
 		targetBottomY = popupLocation.y + popupSize.height;
 
-		// install own event queue to supress mouse events when mouse is moved within safe triangle
+		// install own event queue to suppress mouse events when mouse is moved within safe triangle
 		if( subMenuEventQueue == null )
 			subMenuEventQueue = new SubMenuEventQueue();
 

flatlaf-core/src/main/java/com/formdev/flatlaf/UIDefaultsLoader.java

@@ -161,7 +161,7 @@ class UIDefaultsLoader
 						classLoader = FlatLaf.class.getClassLoader();
 
 					for( Class<?> lafClass : lafClasses ) {
-						String propertiesName = packageName + '/' + lafClass.getSimpleName() + ".properties";
+						String propertiesName = packageName + '/' + simpleClassName( lafClass ) + ".properties";
 						try( InputStream in = classLoader.getResourceAsStream( propertiesName ) ) {
 							if( in != null )
 								properties.load( in );
@@ -171,7 +171,7 @@ class UIDefaultsLoader
 					// load from package URL
 					URL packageUrl = (URL) source;
 					for( Class<?> lafClass : lafClasses ) {
-						URL propertiesUrl = new URL( packageUrl + lafClass.getSimpleName() + ".properties" );
+						URL propertiesUrl = new URL( packageUrl + simpleClassName( lafClass ) + ".properties" );
 
 						try( InputStream in = propertiesUrl.openStream() ) {
 							properties.load( in );
@@ -183,7 +183,7 @@ class UIDefaultsLoader
 					// load from folder
 					File folder = (File) source;
 					for( Class<?> lafClass : lafClasses ) {
-						File propertiesFile = new File( folder, lafClass.getSimpleName() + ".properties" );
+						File propertiesFile = new File( folder, simpleClassName( lafClass ) + ".properties" );
 						if( !propertiesFile.isFile() )
 							continue;
 
@@ -294,6 +294,14 @@ class UIDefaultsLoader
 		}
 	}
 
+	/**
+	 * Similar to Class.getSimpleName(), but includes enclosing class for nested classes.
+	 */
+	static String simpleClassName( Class<?> cls ) {
+		String className = cls.getName();
+		return className.substring( className.lastIndexOf( '.' ) + 1 );
+	}
+
 	static void logParseError( String key, String value, RuntimeException ex, boolean severe ) {
 		String message = "FlatLaf: Failed to parse: '" + key + '=' + value + '\'';
 		if( severe )

flatlaf-core/src/main/java/com/formdev/flatlaf/icons/FlatTabbedPaneCloseIcon.java

@@ -90,7 +90,7 @@ public class FlatTabbedPaneCloseIcon
 				closeSize.width, closeSize.height, closeArc, closeArc );
 		}
 
-		// set cross color
+		// set color of cross
 		Color fg = FlatButtonUI.buttonStateColor( c, closeForeground, null, null, closeHoverForeground, closePressedForeground );
 		g.setColor( FlatUIUtils.deriveColor( fg, c.getForeground() ) );
 

flatlaf-core/src/main/java/com/formdev/flatlaf/icons/FlatTreeOpenIcon.java

@@ -57,11 +57,11 @@ public class FlatTreeOpenIcon
 			double arc = 1.5;
 			double arc2 = 0.5;
 			path = FlatUIUtils.createPath( false,
-				// bottom-left of opend part
+				// bottom-left of opened part
 				2,13.5,
-				// top-left of opend part
+				// top-left of opened part
 				FlatUIUtils.ROUNDED, 4.5,7.5, arc,
-				// top-right of opend part
+				// top-right of opened part
 				FlatUIUtils.ROUNDED, 15.5,7.5, arc2,
 
 				// bottom-right

flatlaf-core/src/main/java/com/formdev/flatlaf/icons/FlatWindowAbstractIcon.java

@@ -71,7 +71,7 @@ public abstract class FlatWindowAbstractIcon
 	protected void paintBackground( Component c, Graphics2D g ) {
 		Color background = FlatButtonUI.buttonStateColor( c, null, null, null, hoverBackground, pressedBackground );
 		if( background != null ) {
-			// disable antialiasing for background rectangle painting to avoid blury edges when scaled (e.g. at 125% or 175%)
+			// disable antialiasing for background rectangle painting to avoid blurry edges when scaled (e.g. at 125% or 175%)
 			Object oldHint = g.getRenderingHint( RenderingHints.KEY_ANTIALIASING );
 			g.setRenderingHint( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_OFF );
 

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatBorder.java

@@ -28,7 +28,6 @@ import javax.swing.JComboBox;
 import javax.swing.JComponent;
 import javax.swing.JScrollPane;
 import javax.swing.JSpinner;
-import javax.swing.JViewport;
 import javax.swing.UIManager;
 import javax.swing.plaf.basic.BasicBorders;
 import com.formdev.flatlaf.FlatClientProperties;
@@ -195,8 +194,7 @@ public class FlatBorder
 	protected boolean isEnabled( Component c ) {
 		if( c instanceof JScrollPane ) {
 			// check whether view component is disabled
-			JViewport viewport = ((JScrollPane)c).getViewport();
-			Component view = (viewport != null) ? viewport.getView() : null;
+			Component view = FlatScrollPaneUI.getView( (JScrollPane) c );
 			if( view != null && !isEnabled( view ) )
 				return false;
 		}

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatButtonUI.java

@@ -53,6 +53,8 @@ import javax.swing.plaf.ToolBarUI;
 import javax.swing.plaf.UIResource;
 import javax.swing.plaf.basic.BasicButtonListener;
 import javax.swing.plaf.basic.BasicButtonUI;
+import javax.swing.plaf.basic.BasicHTML;
+import javax.swing.text.View;
 import com.formdev.flatlaf.FlatClientProperties;
 import com.formdev.flatlaf.FlatLaf;
 import com.formdev.flatlaf.icons.FlatHelpButtonIcon;
@@ -551,9 +553,45 @@ public class FlatButtonUI
 		}
 	}
 
+	/**
+	 * Similar to BasicButtonUI.paint(), but does not use zero insets for HTML text,
+	 * which is done in BasicButtonUI.layout() since Java 19.
+	 * See https://github.com/openjdk/jdk/pull/8407
+	 * and https://github.com/openjdk/jdk/pull/8407#issuecomment-1761583430
+	 */
 	@Override
 	public void paint( Graphics g, JComponent c ) {
-		super.paint( FlatLabelUI.createGraphicsHTMLTextYCorrection( g, c ), c );
+		g = FlatLabelUI.createGraphicsHTMLTextYCorrection( g, c );
+
+		AbstractButton b = (AbstractButton) c;
+
+		// layout
+		String clippedText = layout( b, b.getFontMetrics( b.getFont() ), b.getWidth(), b.getHeight() );
+
+		// not used in FlatLaf, but invoked for compatibility with BasicButtonUI.paint()
+		clearTextShiftOffset();
+
+		// not used in FlatLaf, but invoked for compatibility with BasicButtonUI.paint()
+		ButtonModel model = b.getModel();
+		if( model.isArmed() && model.isPressed() )
+			paintButtonPressed( g, b );
+
+		// paint icon
+		if( b.getIcon() != null )
+			paintIcon( g, b, iconR );
+
+		// paint text
+		if( clippedText != null && !clippedText.isEmpty() ) {
+			View view = (View) b.getClientProperty( BasicHTML.propertyKey );
+			if( view != null )
+				view.paint( g, textR ); // HTML text
+			else
+				paintText( g, b, textR, clippedText );
+		}
+
+		// not used in FlatLaf, but invoked for compatibility with BasicButtonUI.paint()
+		if( b.isFocusPainted() && b.hasFocus() )
+			paintFocus( g, b, viewR, textR, iconR );
 	}
 
 	@Override
@@ -683,14 +721,15 @@ public class FlatButtonUI
 	}
 
 	protected Color getForeground( JComponent c ) {
+		Color fg = c.getForeground();
 		boolean toolBarButton = isToolBarButton( c ) || isBorderlessButton( c );
 
 		// selected state
 		if( ((AbstractButton)c).isSelected() ) {
 			return buttonStateColor( c,
 				toolBarButton
-					? (toolbarSelectedForeground != null ? toolbarSelectedForeground : c.getForeground())
-					: selectedForeground,
+					? (toolbarSelectedForeground != null ? toolbarSelectedForeground : fg)
+					: (isCustomForeground( fg ) ? fg : selectedForeground),
 				toolBarButton
 					? (toolbarDisabledSelectedForeground != null ? toolbarDisabledSelectedForeground : disabledText)
 					: (disabledSelectedForeground != null ? disabledSelectedForeground : disabledText),
@@ -702,7 +741,7 @@ public class FlatButtonUI
 		// toolbar button
 		if( toolBarButton ) {
 			return buttonStateColor( c,
-				c.getForeground(),
+				fg,
 				disabledText,
 				null,
 				toolbarHoverForeground,
@@ -713,7 +752,7 @@ public class FlatButtonUI
 		return buttonStateColor( c,
 			getForegroundBase( c, def ),
 			disabledText,
-			isCustomForeground( c.getForeground() ) ? null : (def ? defaultFocusedForeground : focusedForeground),
+			isCustomForeground( fg ) ? null : (def ? defaultFocusedForeground : focusedForeground),
 			def ? defaultHoverForeground : hoverForeground,
 			def ? defaultPressedForeground : pressedForeground );
 	}
@@ -786,6 +825,67 @@ public class FlatButtonUI
 		return margin instanceof UIResource && Objects.equals( margin, defaultMargin );
 	}
 
+	@Override
+	public int getBaseline( JComponent c, int width, int height ) {
+		return getBaselineImpl( c, width, height );
+	}
+
+	/**
+	 * Similar to BasicButtonUI.getBaseline(), but does not use zero insets for HTML text,
+	 * which is done in BasicButtonUI.layout() since Java 19.
+	 * See https://github.com/openjdk/jdk/pull/8407
+	 * and https://github.com/openjdk/jdk/pull/8407#issuecomment-1761583430
+	 */
+	static int getBaselineImpl( JComponent c, int width, int height ) {
+		if( width < 0 || height < 0 )
+			throw new IllegalArgumentException();
+
+		AbstractButton b = (AbstractButton) c;
+		String text = b.getText();
+		if( text == null || text.isEmpty() )
+			return -1;
+
+		FontMetrics fm = b.getFontMetrics( b.getFont() );
+		layout( b, fm, width, height );
+
+		View view = (View) b.getClientProperty( BasicHTML.propertyKey );
+		if( view != null ) {
+			// HTML text
+			int baseline = BasicHTML.getHTMLBaseline( view, textR.width, textR.height );
+			return (baseline >= 0) ? textR.y + baseline : baseline;
+		} else
+			return textR.y + fm.getAscent();
+	}
+
+	/**
+	 * Similar to BasicButtonUI.layout(), but does not use zero insets for HTML text,
+	 * which is done in BasicButtonUI.layout() since Java 19.
+	 * See https://github.com/openjdk/jdk/pull/8407
+	 * and https://github.com/openjdk/jdk/pull/8407#issuecomment-1761583430
+	 */
+	private static String layout( AbstractButton b, FontMetrics fm, int width, int height ) {
+		// compute view rectangle
+		Insets insets = b.getInsets();
+		viewR.setBounds( insets.left, insets.top,
+			width - insets.left - insets.right,
+			height - insets.top - insets.bottom );
+
+		// reset rectangles
+		textR.setBounds( 0, 0, 0, 0 );
+		iconR.setBounds( 0, 0, 0, 0 );
+
+		String text = b.getText();
+		return SwingUtilities.layoutCompoundLabel( b, fm, text, b.getIcon(),
+			b.getVerticalAlignment(), b.getHorizontalAlignment(),
+			b.getVerticalTextPosition(), b.getHorizontalTextPosition(),
+			viewR, iconR, textR,
+			(text != null) ? b.getIconTextGap() : 0 );
+	}
+
+	private static Rectangle viewR = new Rectangle();
+	private static Rectangle textR = new Rectangle();
+	private static Rectangle iconR = new Rectangle();
+
 	//---- class FlatButtonListener -------------------------------------------
 
 	protected class FlatButtonListener

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatComboBoxUI.java

@@ -926,7 +926,7 @@ public class FlatComboBoxUI
 		protected void configurePopup() {
 			super.configurePopup();
 
-			// make opaque to avoid that background shines thru border (e.g. at 150% scaling)
+			// make opaque to avoid that background shines through border (e.g. at 150% scaling)
 			setOpaque( true );
 
 			// set popup border
@@ -944,7 +944,7 @@ public class FlatComboBoxUI
 			if( popupBackground != null )
 				list.setBackground( popupBackground );
 
-			// set popup background because it may shine thru when scaled (e.g. at 150%)
+			// set popup background because it may shine through when scaled (e.g. at 150%)
 			// use non-UIResource to avoid that it is overwritten when making
 			// popup visible (see JPopupMenu.setInvoker()) in theme editor preview
 			setBackground( FlatUIUtils.nonUIResource( list.getBackground() ) );
@@ -1090,7 +1090,7 @@ public class FlatComboBoxUI
 		}
 
 		// using synchronized to avoid problems with code that modifies combo box
-		// (model, selection, etc) not on AWT thread (which should be not done)
+		// (model, selection, etc.) not on AWT thread (which should be not done)
 		synchronized void install( Component c, int focusWidth ) {
 			if( !(c instanceof JComponent) )
 				return;
@@ -1242,7 +1242,7 @@ public class FlatComboBoxUI
 	 * Key selection manager that delegates to the default manager.
 	 * Shows the popup if Space key is pressed and "typed characters" buffer is empty.
 	 * If items contain spaces (e.g. "a b") it is still possible to select them
-	 * by pressing keys a, Space and b.
+	 * by pressing keys 'a', 'Space' and 'b'.
 	 */
 	private class FlatKeySelectionManager
 		implements JComboBox.KeySelectionManager, UIResource

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatFileChooserUI.java

@@ -370,7 +370,11 @@ public class FlatFileChooserUI
 
 			// get system icon
 			if( f != null ) {
+				try {
 					icon = getFileChooser().getFileSystemView().getSystemIcon( f );
+				} catch( NullPointerException ex ) {
+					// Java 21 may throw a NPE for exe files that use default Windows exe icon
+				}
 
 				if( icon != null ) {
 					if( icon instanceof ImageIcon )
@@ -425,7 +429,7 @@ public class FlatFileChooserUI
 			iconFunction = (Function<File, Icon>) UIManager.get( "FileChooser.shortcuts.iconFunction" );
 
 			FileSystemView fsv = fc.getFileSystemView();
-			File[] files = getChooserShortcutPanelFiles( fsv );
+			File[] files = JavaCompatibility2.getChooserShortcutPanelFiles( fsv );
 			if( filesFunction != null )
 				files = filesFunction.apply( files );
 
@@ -494,32 +498,6 @@ public class FlatFileChooserUI
 			return button;
 		}
 
-		protected File[] getChooserShortcutPanelFiles( FileSystemView fsv ) {
-			try {
-				if( SystemInfo.isJava_12_orLater ) {
-					Method m = fsv.getClass().getMethod( "getChooserShortcutPanelFiles" );
-					File[] files = (File[]) m.invoke( fsv );
-
-					// on macOS and Linux, files consists only of the user home directory
-					if( files.length == 1 && files[0].equals( new File( System.getProperty( "user.home" ) ) ) )
-						files = new File[0];
-
-					return files;
-				} else if( SystemInfo.isWindows ) {
-					Class<?> cls = Class.forName( "sun.awt.shell.ShellFolder" );
-					Method m = cls.getMethod( "get", String.class );
-					return (File[]) m.invoke( null, "fileChooserShortcutPanelFolders" );
-				}
-			} catch( IllegalAccessException ex ) {
-				// do not log because access may be denied via VM option '--illegal-access=deny'
-			} catch( Exception ex ) {
-				LoggingFacade.INSTANCE.logSevere( null, ex );
-			}
-
-			// fallback
-			return new File[0];
-		}
-
 		protected String getDisplayName( FileSystemView fsv, File file ) {
 			if( displayNameFunction != null ) {
 				String name = displayNameFunction.apply( file );
@@ -540,6 +518,7 @@ public class FlatFileChooserUI
 			if( doNotUseSystemIcons() )
 				return new FlatFileViewDirectoryIcon();
 
+			try {
 				// Java 17+ supports getting larger system icons
 				try {
 					if( SystemInfo.isJava_17_orLater ) {
@@ -555,14 +534,20 @@ public class FlatFileChooserUI
 								return new ImageIcon( image );
 						}
 					}
-			} catch( IllegalAccessException ex ) {
-				// do not log because access may be denied via VM option '--illegal-access=deny'
 				} catch( Exception ex ) {
+					// do not log InaccessibleObjectException because access
+					// may be denied via VM option '--illegal-access=deny' (default in Java 16)
+					// (not catching InaccessibleObjectException here because it is new in Java 9, but FlatLaf also runs on Java 8)
+					if( !"java.lang.reflect.InaccessibleObjectException".equals( ex.getClass().getName() ) )
 						LoggingFacade.INSTANCE.logSevere( null, ex );
 				}
 
 				// get system icon in default size 16x16
 				return fsv.getSystemIcon( file );
+			} catch( NullPointerException ex ) {
+				// Java 21 may throw a NPE for exe files that use default Windows exe icon
+				return new FlatFileViewDirectoryIcon();
+			}
 		}
 
 		protected void directoryChanged( File file ) {

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatLineBorder.java

@@ -22,6 +22,7 @@ import java.awt.Component;
 import java.awt.Graphics;
 import java.awt.Graphics2D;
 import java.awt.Insets;
+import javax.swing.JComponent;
 
 /**
  * Line border for various components.
@@ -66,6 +67,9 @@ public class FlatLineBorder
 
 	@Override
 	public void paintBorder( Component c, Graphics g, int x, int y, int width, int height ) {
+		if( c instanceof JComponent && ((JComponent)c).getClientProperty( FlatPopupFactory.KEY_POPUP_USES_NATIVE_BORDER ) != null )
+			return;
+
 		Graphics2D g2 = (Graphics2D) g.create();
 		try {
 			FlatUIUtils.setRenderingHints( g2 );

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatListUI.java

@@ -411,7 +411,7 @@ public class FlatListUI
 				int leftIndex = locationToIndex( list, new Point( r.x - 1, r.y ) );
 				int rightIndex = locationToIndex( list, new Point( r.x + r.width, r.y ) );
 
-				// special handling for the case that last column contains less cells than the other columns
+				// special handling for the case that last column contains fewer cells than the other columns
 				boolean ltr = list.getComponentOrientation().isLeftToRight();
 				if( !ltr && leftIndex >= 0 && leftIndex != row && leftIndex == locationToIndex( list, new Point( r.x - 1, r.y - 1 ) ) )
 					leftIndex = -1;

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatMenuBarUI.java

@@ -27,7 +27,6 @@ import java.awt.event.ActionEvent;
 import java.beans.PropertyChangeListener;
 import java.util.Map;
 import java.util.concurrent.atomic.AtomicBoolean;
-import javax.swing.AbstractAction;
 import javax.swing.ActionMap;
 import javax.swing.BoxLayout;
 import javax.swing.JComponent;
@@ -39,7 +38,6 @@ import javax.swing.MenuElement;
 import javax.swing.MenuSelectionManager;
 import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
-import javax.swing.plaf.ActionMapUIResource;
 import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.UIResource;
 import javax.swing.plaf.basic.BasicMenuBarUI;
@@ -144,12 +142,10 @@ public class FlatMenuBarUI
 	protected void installKeyboardActions() {
 		super.installKeyboardActions();
 
+		// get shared action map, used for all menu bars
 		ActionMap map = SwingUtilities.getUIActionMap( menuBar );
-		if( map == null ) {
-			map = new ActionMapUIResource();
-			SwingUtilities.replaceUIActionMap( menuBar, map );
-		}
-		map.put( "takeFocus", new TakeFocus() );
+		if( map != null && !(map.get( "takeFocus" ) instanceof TakeFocusAction) )
+			map.put( "takeFocus", new TakeFocusAction( "takeFocus" ) );
 	}
 
 	/** @since 2 */
@@ -365,16 +361,20 @@ public class FlatMenuBarUI
 		}
 	}
 
-	//---- class TakeFocus ----------------------------------------------------
+	//---- class TakeFocusAction ----------------------------------------------
 
 	/**
 	 * Activates the menu bar and shows mnemonics.
 	 * On Windows, the popup of the first menu is not shown.
 	 * On other platforms, the popup of the first menu is shown.
 	 */
-	private static class TakeFocus
-		extends AbstractAction
+	private static class TakeFocusAction
+		extends FlatUIAction
 	{
+		TakeFocusAction( String name ) {
+			super( name );
+		}
+
 		@Override
 		public void actionPerformed( ActionEvent e ) {
 			JMenuBar menuBar = (JMenuBar) e.getSource();

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatMenuUI.java

@@ -17,6 +17,7 @@
 package com.formdev.flatlaf.ui;
 
 import java.awt.Color;
+import java.awt.Container;
 import java.awt.Dimension;
 import java.awt.Font;
 import java.awt.Graphics;
@@ -271,7 +272,7 @@ public class FlatMenuUI
 				if( !isHover() )
 					selectionBackground = getStyleFromMenuBarUI( ui -> ui.selectionBackground, menuBarSelectionBackground, selectionBackground );
 
-				JMenuBar menuBar = (JMenuBar) menuItem.getParent();
+				Container menuBar = menuItem.getParent();
 				JRootPane rootPane = SwingUtilities.getRootPane( menuBar );
 				if( rootPane != null && rootPane.getParent() instanceof Window &&
 					rootPane.getJMenuBar() == menuBar &&
@@ -321,12 +322,17 @@ public class FlatMenuUI
 		}
 
 		private <T> T getStyleFromMenuBarUI( Function<FlatMenuBarUI, T> f, T defaultValue ) {
-			MenuBarUI ui = ((JMenuBar)menuItem.getParent()).getUI();
-			if( !(ui instanceof FlatMenuBarUI) )
-				return defaultValue;
-
+			Container menuItemParent = menuItem.getParent();
+			if( menuItemParent instanceof JMenuBar ) {
+				MenuBarUI ui = ((JMenuBar) menuItemParent).getUI();
+				if( ui instanceof FlatMenuBarUI ) {
 					T value = f.apply( (FlatMenuBarUI) ui );
-			return (value != null) ? value : defaultValue;
+					if( value != null ) {
+						return value;
+					}
+				}
+			}
+			return defaultValue;
 		}
 	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatNativeLibrary.java

@@ -22,6 +22,7 @@ import java.security.CodeSource;
 import com.formdev.flatlaf.FlatSystemProperties;
 import com.formdev.flatlaf.util.LoggingFacade;
 import com.formdev.flatlaf.util.NativeLibrary;
+import com.formdev.flatlaf.util.StringUtils;
 import com.formdev.flatlaf.util.SystemInfo;
 
 /**
@@ -36,16 +37,18 @@ class FlatNativeLibrary
 	private static boolean initialized;
 	private static NativeLibrary nativeLibrary;
 
+	private native static int getApiVersion();
+
 	/**
 	 * Loads native library (if available) and returns whether loaded successfully.
 	 * Returns {@code false} if no native library is available.
 	 */
-	static synchronized boolean isLoaded() {
-		initialize();
+	static synchronized boolean isLoaded( int apiVersion ) {
+		initialize( apiVersion );
 		return (nativeLibrary != null) ? nativeLibrary.isLoaded() : false;
 	}
 
-	private static void initialize() {
+	private static void initialize( int apiVersion ) {
 		if( initialized )
 			return;
 		initialized = true;
@@ -78,9 +81,15 @@ class FlatNativeLibrary
 			//
 			// To avoid this, flatlaf.dll is not linked to jawt.dll,
 			// which avoids loading jawt.dll when flatlaf.dll is loaded.
-			// Instead flatlaf.dll dynamically loads jawt.dll when first used,
+			// Instead, flatlaf.dll dynamically loads jawt.dll when first used,
 			// which is guaranteed after AWT initialization.
 
+		} else if( SystemInfo.isMacOS_10_14_Mojave_orLater && (SystemInfo.isAARCH64 || SystemInfo.isX86_64) ) {
+			// macOS: requires macOS 10.14 or later (arm64 or x86_64)
+
+			classifier = SystemInfo.isAARCH64 ? "macos-arm64" : "macos-x86_64";
+			ext = "dylib";
+
 		} else if( SystemInfo.isLinux && SystemInfo.isX86_64 ) {
 			// Linux: requires x86_64
 
@@ -97,7 +106,26 @@ class FlatNativeLibrary
 			return; // no native library available for current OS or CPU architecture
 
 		// load native library
-		nativeLibrary = createNativeLibrary( classifier, ext );
+		NativeLibrary nativeLibrary = createNativeLibrary( classifier, ext );
+		if( !nativeLibrary.isLoaded() )
+			return;
+
+		// check API version (and check whether library works)
+		try {
+			int actualApiVersion = getApiVersion();
+			if( actualApiVersion != apiVersion ) {
+				LoggingFacade.INSTANCE.logSevere( "FlatLaf: Wrong API version in native library (expected "
+					+ apiVersion + ", actual " + actualApiVersion + "). Ignoring native library.", null );
+				return;
+			}
+		} catch( Throwable ex ) {
+			// could be a UnsatisfiedLinkError in case that loading native library
+			// from temp directory was blocked by some OS security mechanism
+			LoggingFacade.INSTANCE.logSevere( "FlatLaf: Failed to get API version of native library. Ignoring native library.", ex );
+			return;
+		}
+
+		FlatNativeLibrary.nativeLibrary = nativeLibrary;
 	}
 
 	private static NativeLibrary createNativeLibrary( String classifier, String ext ) {
@@ -111,13 +139,32 @@ class FlatNativeLibrary
 				if( library.isLoaded() )
 					return library;
 
-				LoggingFacade.INSTANCE.logSevere( "Did not find library " + libraryName + " in java.library.path, using extracted library instead", null );
+				LoggingFacade.INSTANCE.logSevere( "FlatLaf: Native library '" + System.mapLibraryName( libraryName )
+					+ "' not found in java.library.path '" + System.getProperty( "java.library.path" )
+					+ "'. Using extracted native library instead.", null );
 			} else {
+				// try standard library naming scheme
+				// (same as in flatlaf.jar in package 'com/formdev/flatlaf/natives')
 				File libraryFile = new File( libraryPath, System.mapLibraryName( libraryName ) );
 				if( libraryFile.exists() )
 					return new NativeLibrary( libraryFile, true );
 
-				LoggingFacade.INSTANCE.logSevere( "Did not find external library " + libraryFile + ", using extracted library instead", null );
+				// try Maven naming scheme
+				// (see https://www.formdev.com/flatlaf/native-libraries/)
+				String libraryName2 = null;
+				File jarFile = getJarFile();
+				if( jarFile != null ) {
+					libraryName2 = buildLibraryName( jarFile, classifier, ext );
+					File libraryFile2 = new File( libraryPath, libraryName2 );
+					if( libraryFile2.exists() )
+						return new NativeLibrary( libraryFile2, true );
+				}
+
+				LoggingFacade.INSTANCE.logSevere( "FlatLaf: Native library '"
+					+ libraryFile.getName()
+					+ (libraryName2 != null ? ("' or '" + libraryName2) : "")
+					+ "' not found in '" + libraryFile.getParentFile().getAbsolutePath()
+					+ "'. Using extracted native library instead.", null );
 			}
 		}
 
@@ -145,6 +192,51 @@ class FlatNativeLibrary
 	 *     flatlaf-3.1-linux-x86_64.so
 	 */
 	private static File findLibraryBesideJar( String classifier, String ext ) {
+		// get location of FlatLaf jar (or fat/uber application jar)
+		File jarFile = getJarFile();
+		if( jarFile == null )
+			return null;
+
+		// build library file
+		String libraryName = buildLibraryName( jarFile, classifier, ext );
+		File jarDir = jarFile.getParentFile();
+
+		// check whether native library exists in same directory as jar
+		File libraryFile = new File( jarDir, libraryName );
+		if( libraryFile.isFile() )
+			return libraryFile;
+
+		// if jar is in "lib" directory, then also check whether native library exists
+		// in "../bin" directory
+		if( jarDir.getName().equalsIgnoreCase( "lib" ) ) {
+			libraryFile = new File( jarDir.getParentFile(), "bin/" + libraryName );
+			if( libraryFile.isFile() )
+				return libraryFile;
+		}
+
+		// special case: support Gradle cache when running in development environment
+		//   <user-home>/.gradle/caches/modules-2/files-2.1/com.formdev/flatlaf/<version>/<hash-1>/flatlaf-<version>.jar
+		//   <user-home>/.gradle/caches/modules-2/files-2.1/com.formdev/flatlaf/<version>/<hash-2>/flatlaf-<version>-windows-x86_64.dll
+		String path = jarDir.getAbsolutePath().replace( '\\', '/' );
+		if( path.contains( "/.gradle/caches/" ) ) {
+			File versionDir = jarDir.getParentFile();
+			if( libraryName.contains( versionDir.getName() ) ) {
+				File[] dirs = versionDir.listFiles();
+				if( dirs != null ) {
+					for( File dir : dirs ) {
+						libraryFile = new File( dir, libraryName );
+						if( libraryFile.isFile() )
+							return libraryFile;
+					}
+				}
+			}
+		}
+
+		// native library not found
+		return null;
+	}
+
+	private static File getJarFile() {
 		try {
 			// get location of FlatLaf jar
 			CodeSource codeSource = FlatNativeLibrary.class.getProtectionDomain().getCodeSource();
@@ -162,31 +254,23 @@ class FlatNativeLibrary
 			if( !jarFile.isFile() )
 				return null;
 
-			// build library file
-			String jarName = jarFile.getName();
-			String jarBasename = jarName.substring( 0, jarName.lastIndexOf( '.' ) );
-			File parent = jarFile.getParentFile();
-			String libraryName = jarBasename
-				+ (jarBasename.contains( "flatlaf" ) ? "" : "-flatlaf")
-				+ '-' + classifier + '.' + ext;
-
-			// check whether native library exists in same directory as jar
-			File libraryFile = new File( parent, libraryName );
-			if( libraryFile.isFile() )
-				return libraryFile;
-
-			// if jar is in "lib" directory, then also check whether library exists
-			// in "../bin" directory
-			if( parent.getName().equalsIgnoreCase( "lib" ) ) {
-				libraryFile = new File( parent.getParentFile(), "bin/" + libraryName );
-				if( libraryFile.isFile() )
-					return libraryFile;
-			}
+			return jarFile;
 		} catch( Exception ex ) {
 			LoggingFacade.INSTANCE.logSevere( ex.getMessage(), ex );
+			return null;
+		}
 	}
 
-		return null;
+	private static String buildLibraryName( File jarFile, String classifier, String ext ) {
+		String jarName = jarFile.getName();
+		String jarBasename = jarName.substring( 0, jarName.lastIndexOf( '.' ) );
+
+		// remove classifier "no-natives" (if used)
+		jarBasename = StringUtils.removeTrailing( jarBasename, "-no-natives" );
+
+		return jarBasename
+			+ (jarBasename.contains( "flatlaf" ) ? "" : "-flatlaf")
+			+ '-' + classifier + '.' + ext;
 	}
 
 	private static void loadJAWT() {

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatNativeLinuxLibrary.java

@@ -35,8 +35,16 @@ import com.formdev.flatlaf.util.SystemInfo;
  */
 class FlatNativeLinuxLibrary
 {
+	private static int API_VERSION_LINUX = 3001;
+
+	/**
+	 * Checks whether native library is loaded/available.
+	 * <p>
+	 * <b>Note</b>: It is required to invoke this method before invoking any other
+	 *              method of this class. Otherwise, the native library may not be loaded.
+	 */
 	static boolean isLoaded() {
-		return SystemInfo.isLinux && FlatNativeLibrary.isLoaded();
+		return SystemInfo.isLinux && FlatNativeLibrary.isLoaded( API_VERSION_LINUX );
 	}
 
 	// direction for _NET_WM_MOVERESIZE message

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatNativeMacLibrary.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2023 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.formdev.flatlaf.ui;
+
+import java.awt.Rectangle;
+import java.awt.Window;
+import com.formdev.flatlaf.util.SystemInfo;
+
+/**
+ * Native methods for macOS.
+ * <p>
+ * <b>Note</b>: This is private API. Do not use!
+ *
+ * <h2>Methods that use windows as parameter</h2>
+ *
+ * For all methods that accept a {@link java.awt.Window} as parameter,
+ * the underlying macOS window must be already created,
+ * otherwise the method fails. You can use following to ensure this:
+ * <pre>{@code
+ * if( !window.isDisplayable() )
+ *     window.addNotify();
+ * }</pre>
+ * or invoke the method after packing the window. E.g.
+ * <pre>{@code
+ * window.pack();
+ * }</pre>
+ *
+ * @author Karl Tauber
+ * @since 3.3
+ */
+public class FlatNativeMacLibrary
+{
+	private static int API_VERSION_MACOS = 2001;
+
+	/**
+	 * Checks whether native library is loaded/available.
+	 * <p>
+	 * <b>Note</b>: It is required to invoke this method before invoking any other
+	 *              method of this class. Otherwise, the native library may not be loaded.
+	 */
+	public static boolean isLoaded() {
+		return SystemInfo.isMacOS && FlatNativeLibrary.isLoaded( API_VERSION_MACOS );
+	}
+
+	public native static boolean setWindowRoundedBorder( Window window, float radius, float borderWidth, int borderColor );
+
+	/** @since 3.4 */
+	public static final int
+		BUTTONS_SPACING_DEFAULT = 0,
+		BUTTONS_SPACING_MEDIUM = 1,
+		BUTTONS_SPACING_LARGE = 2;
+
+	/** @since 3.4 */ public native static boolean setWindowButtonsSpacing( Window window, int buttonsSpacing );
+	/** @since 3.4 */ public native static Rectangle getWindowButtonsBounds( Window window );
+	/** @since 3.4 */ public native static boolean isWindowFullScreen( Window window );
+	/** @since 3.4 */ public native static boolean toggleWindowFullScreen( Window window );
+}

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatNativeWindowBorder.java

@@ -17,20 +17,27 @@
 package com.formdev.flatlaf.ui;
 
 import java.awt.Color;
+import java.awt.Component;
 import java.awt.Container;
+import java.awt.Graphics;
+import java.awt.Graphics2D;
+import java.awt.Point;
 import java.awt.Rectangle;
+import java.awt.Toolkit;
 import java.awt.Window;
 import java.beans.PropertyChangeListener;
-import java.util.List;
+import java.util.function.Predicate;
 import javax.swing.JDialog;
 import javax.swing.JFrame;
 import javax.swing.JRootPane;
+import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
 import javax.swing.event.ChangeListener;
+import javax.swing.plaf.BorderUIResource;
 import com.formdev.flatlaf.FlatClientProperties;
 import com.formdev.flatlaf.FlatLaf;
 import com.formdev.flatlaf.FlatSystemProperties;
-import com.formdev.flatlaf.ui.JBRCustomDecorations.JBRWindowTopBorder;
+import com.formdev.flatlaf.util.HiDPIUtils;
 import com.formdev.flatlaf.util.SystemInfo;
 
 /**
@@ -54,27 +61,15 @@ public class FlatNativeWindowBorder
 		!SystemInfo.isWinPE &&
 		FlatSystemProperties.getBoolean( FlatSystemProperties.USE_WINDOW_DECORATIONS, true );
 
-	// check this field before using class JBRCustomDecorations to avoid unnecessary loading of that class
-	private static final boolean canUseJBRCustomDecorations =
-		canUseWindowDecorations &&
-		SystemInfo.isJetBrainsJVM_11_orLater &&
-		FlatSystemProperties.getBoolean( FlatSystemProperties.USE_JETBRAINS_CUSTOM_DECORATIONS, false );
-
 	private static Boolean supported;
 	private static Provider nativeProvider;
 
 	public static boolean isSupported() {
-		if( canUseJBRCustomDecorations )
-			return JBRCustomDecorations.isSupported();
-
 		initialize();
 		return supported;
 	}
 
 	static Object install( JRootPane rootPane ) {
-		if( canUseJBRCustomDecorations )
-			return JBRCustomDecorations.install( rootPane );
-
 		if( !isSupported() )
 			return null;
 
@@ -163,11 +158,6 @@ public class FlatNativeWindowBorder
 	}
 
 	static void uninstall( JRootPane rootPane, Object data ) {
-		if( canUseJBRCustomDecorations ) {
-			JBRCustomDecorations.uninstall( rootPane, data );
-			return;
-		}
-
 		if( !isSupported() )
 			return;
 
@@ -215,9 +205,6 @@ public class FlatNativeWindowBorder
 	}
 
 	public static boolean hasCustomDecoration( Window window ) {
-		if( canUseJBRCustomDecorations )
-			return JBRCustomDecorations.hasCustomDecoration( window );
-
 		if( !isSupported() )
 			return false;
 
@@ -225,11 +212,6 @@ public class FlatNativeWindowBorder
 	}
 
 	public static void setHasCustomDecoration( Window window, boolean hasCustomDecoration ) {
-		if( canUseJBRCustomDecorations ) {
-			JBRCustomDecorations.setHasCustomDecoration( window, hasCustomDecoration );
-			return;
-		}
-
 		if( !isSupported() )
 			return;
 
@@ -237,23 +219,18 @@ public class FlatNativeWindowBorder
 	}
 
 	static void setTitleBarHeightAndHitTestSpots( Window window, int titleBarHeight,
-		List<Rectangle> hitTestSpots, Rectangle appIconBounds, Rectangle minimizeButtonBounds,
+		Predicate<Point> captionHitTestCallback, Rectangle appIconBounds, Rectangle minimizeButtonBounds,
 		Rectangle maximizeButtonBounds, Rectangle closeButtonBounds )
 	{
-		if( canUseJBRCustomDecorations ) {
-			JBRCustomDecorations.setTitleBarHeightAndHitTestSpots( window, titleBarHeight, hitTestSpots );
-			return;
-		}
-
 		if( !isSupported() )
 			return;
 
-		nativeProvider.updateTitleBarInfo( window, titleBarHeight, hitTestSpots,
+		nativeProvider.updateTitleBarInfo( window, titleBarHeight, captionHitTestCallback,
 			appIconBounds, minimizeButtonBounds, maximizeButtonBounds, closeButtonBounds );
 	}
 
 	static boolean showWindow( Window window, int cmd ) {
-		if( canUseJBRCustomDecorations || !isSupported() )
+		if( !isSupported() )
 			return false;
 
 		return nativeProvider.showWindow( window, cmd );
@@ -294,7 +271,7 @@ public class FlatNativeWindowBorder
 	{
 		boolean hasCustomDecoration( Window window );
 		void setHasCustomDecoration( Window window, boolean hasCustomDecoration );
-		void updateTitleBarInfo( Window window, int titleBarHeight, List<Rectangle> hitTestSpots,
+		void updateTitleBarInfo( Window window, int titleBarHeight, Predicate<Point> captionHitTestCallback,
 			Rectangle appIconBounds, Rectangle minimizeButtonBounds, Rectangle maximizeButtonBounds,
 			Rectangle closeButtonBounds );
 
@@ -320,20 +297,36 @@ public class FlatNativeWindowBorder
 	 * No longer needed since Windows 11.
 	 */
 	static class WindowTopBorder
-		extends JBRCustomDecorations.JBRWindowTopBorder
+		extends BorderUIResource.EmptyBorderUIResource
 	{
 		private static WindowTopBorder instance;
 
-		static JBRWindowTopBorder getInstance() {
-			if( canUseJBRCustomDecorations )
-				return JBRWindowTopBorder.getInstance();
+		private final Color activeLightColor = new Color( 0x707070 );
+		private final Color activeDarkColor = new Color( 0x2D2E2F );
+		private final Color inactiveLightColor = new Color( 0xaaaaaa );
+		private final Color inactiveDarkColor = new Color( 0x494A4B );
 
+		private boolean colorizationAffectsBorders;
+		private Color activeColor;
+
+		static WindowTopBorder getInstance() {
 			if( instance == null )
 				instance = new WindowTopBorder();
 			return instance;
 		}
 
-		@Override
+		WindowTopBorder() {
+			super( 1, 0, 0, 0 );
+
+			update();
+			installListeners();
+        }
+
+        void update() {
+			colorizationAffectsBorders = isColorizationColorAffectsBorders();
+			activeColor = calculateActiveBorderColor();
+		}
+
 		void installListeners() {
 			nativeProvider.addChangeListener( e -> {
 				update();
@@ -346,19 +339,69 @@ public class FlatNativeWindowBorder
 			} );
 		}
 
-		@Override
 		boolean isColorizationColorAffectsBorders() {
 			return nativeProvider.isColorizationColorAffectsBorders();
 		}
 
-		@Override
 		Color getColorizationColor() {
 			return nativeProvider.getColorizationColor();
 		}
 
-		@Override
 		int getColorizationColorBalance() {
 			return nativeProvider.getColorizationColorBalance();
 		}
+
+		private Color calculateActiveBorderColor() {
+			if( !colorizationAffectsBorders )
+				return null;
+
+			Color colorizationColor = getColorizationColor();
+			if( colorizationColor != null ) {
+				int colorizationColorBalance = getColorizationColorBalance();
+				if( colorizationColorBalance < 0 || colorizationColorBalance > 100 )
+					colorizationColorBalance = 100;
+
+				if( colorizationColorBalance == 0 )
+					return new Color( 0xD9D9D9 );
+				if( colorizationColorBalance == 100 )
+					return colorizationColor;
+
+				float alpha = colorizationColorBalance / 100.0f;
+				float remainder = 1 - alpha;
+				int r = Math.round( colorizationColor.getRed() * alpha + 0xD9 * remainder );
+				int g = Math.round( colorizationColor.getGreen() * alpha + 0xD9 * remainder );
+				int b = Math.round( colorizationColor.getBlue() * alpha + 0xD9 * remainder );
+
+				// avoid potential IllegalArgumentException in Color constructor
+				r = Math.min( Math.max( r, 0 ), 255 );
+				g = Math.min( Math.max( g, 0 ), 255 );
+				b = Math.min( Math.max( b, 0 ), 255 );
+
+				return new Color( r, g, b );
+			}
+
+			Color activeBorderColor = (Color) Toolkit.getDefaultToolkit().getDesktopProperty( "win.frame.activeBorderColor" );
+			return (activeBorderColor != null) ? activeBorderColor : UIManager.getColor( "MenuBar.borderColor" );
+		}
+
+		@Override
+		public void paintBorder( Component c, Graphics g, int x, int y, int width, int height ) {
+			Window window = SwingUtilities.windowForComponent( c );
+			boolean active = window != null && window.isActive();
+			boolean dark = FlatLaf.isLafDark();
+
+			g.setColor( active
+				? (activeColor != null ? activeColor : (dark ? activeDarkColor : activeLightColor))
+				: (dark ? inactiveDarkColor : inactiveLightColor) );
+			HiDPIUtils.paintAtScale1x( (Graphics2D) g, x, y, width, height, this::paintImpl );
+		}
+
+		private void paintImpl( Graphics2D g, int x, int y, int width, int height, double scaleFactor ) {
+			g.fillRect( x, y, width, 1 );
+		}
+
+		void repaintBorder( Component c ) {
+			c.repaint( 0, 0, c.getWidth(), 1 );
+		}
 	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatNativeWindowsLibrary.java

@@ -16,6 +16,7 @@
 
 package com.formdev.flatlaf.ui;
 
+import java.awt.Color;
 import java.awt.Window;
 import com.formdev.flatlaf.util.SystemInfo;
 
@@ -29,10 +30,18 @@ import com.formdev.flatlaf.util.SystemInfo;
  */
 public class FlatNativeWindowsLibrary
 {
+	private static int API_VERSION_WINDOWS = 1001;
+
 	private static long osBuildNumber = Long.MIN_VALUE;
 
+	/**
+	 * Checks whether native library is loaded/available.
+	 * <p>
+	 * <b>Note</b>: It is required to invoke this method before invoking any other
+	 *              method of this class. Otherwise, the native library may not be loaded.
+	 */
 	public static boolean isLoaded() {
-		return SystemInfo.isWindows && FlatNativeLibrary.isLoaded();
+		return SystemInfo.isWindows && FlatNativeLibrary.isLoaded( API_VERSION_WINDOWS );
 	}
 
 	/**
@@ -93,15 +102,60 @@ public class FlatNativeWindowsLibrary
 	public native static boolean setWindowCornerPreference( long hwnd, int cornerPreference );
 
 	/**
-	 * Sets the color of the window border.
-	 * The red/green/blue values must be in range {@code 0 - 255}.
-	 * If red is {@code -1}, then the system default border color is used (useful to reset the border color).
-	 * If red is {@code -2}, then no border is painted.
-	 * <p>
-	 * Invokes Win32 API method {@code DwmSetWindowAttribute(DWMWA_BORDER_COLOR)}.
+	 * DWMWINDOWATTRIBUTE
+	 * see https://learn.microsoft.com/en-us/windows/win32/api/dwmapi/ne-dwmapi-dwmwindowattribute
+	 *
+	 * @since 3.3
+	 */
+	public static final int
+		DWMWA_USE_IMMERSIVE_DARK_MODE = 20,
+		DWMWA_BORDER_COLOR = 34,
+		DWMWA_CAPTION_COLOR = 35,
+		DWMWA_TEXT_COLOR = 36;
+
+	/**
+	 * Invokes Win32 API method {@code DwmSetWindowAttribute()} with a {@code BOOL} attribute value.
+	 * See https://learn.microsoft.com/en-us/windows/win32/api/dwmapi/nf-dwmapi-dwmsetwindowattribute
+	 *
+	 * @since 3.3
+	 */
+	public native static boolean dwmSetWindowAttributeBOOL( long hwnd, int attribute, boolean value );
+
+	/**
+	 * Invokes Win32 API method {@code DwmSetWindowAttribute()} with a {@code DWORD} attribute value.
+	 * See https://learn.microsoft.com/en-us/windows/win32/api/dwmapi/nf-dwmapi-dwmsetwindowattribute
+	 *
+	 * @since 3.3
+	 */
+	public native static boolean dwmSetWindowAttributeDWORD( long hwnd, int attribute, int value );
+
+	/** @since 3.3 */
+	public static final int
+		// use this constant to reset any window part colors to the system default behavior
+		DWMWA_COLOR_DEFAULT = 0xFFFFFFFF,
+		// use this constant to specify that a window part should not be rendered
+		DWMWA_COLOR_NONE = 0xFFFFFFFE;
+
+	/** @since 3.3 */
+	public static final Color COLOR_NONE = new Color( 0, true );
+
+	/**
+	 * Invokes Win32 API method {@code DwmSetWindowAttribute()} with a {@code COLORREF} attribute value.
 	 * See https://learn.microsoft.com/en-us/windows/win32/api/dwmapi/nf-dwmapi-dwmsetwindowattribute
 	 * <p>
 	 * Supported since Windows 11 Build 22000.
+	 *
+	 * @since 3.3
 	 */
-	public native static boolean setWindowBorderColor( long hwnd, int red, int green, int blue );
+	public static boolean dwmSetWindowAttributeCOLORREF( long hwnd, int attribute, Color color ) {
+		// convert color to Windows RGB value
+		int rgb = (color == COLOR_NONE)
+			? DWMWA_COLOR_NONE
+			: (color != null
+				? (color.getRed() | (color.getGreen() << 8) | (color.getBlue() << 16))
+				: DWMWA_COLOR_DEFAULT);
+
+		// DwmSetWindowAttribute() expects COLORREF as attribute value, which is defined as DWORD
+		return dwmSetWindowAttributeDWORD( hwnd, attribute, rgb );
+	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatOptionPaneUI.java

@@ -30,9 +30,7 @@ import javax.swing.JPanel;
 import javax.swing.JRootPane;
 import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
-import javax.swing.border.Border;
 import javax.swing.plaf.ComponentUI;
-import javax.swing.plaf.UIResource;
 import javax.swing.plaf.basic.BasicHTML;
 import javax.swing.plaf.basic.BasicOptionPaneUI;
 import com.formdev.flatlaf.FlatClientProperties;
@@ -115,13 +113,6 @@ public class FlatOptionPaneUI
 		sameSizeButtons = FlatUIUtils.getUIBoolean( "OptionPane.sameSizeButtons", true );
 	}
 
-	@Override
-	protected void installComponents() {
-		super.installComponents();
-
-		updateChildPanels( optionPane );
-	}
-
 	@Override
 	protected PropertyChangeListener createPropertyChangeListener() {
 		PropertyChangeListener superListener = super.createPropertyChangeListener();
@@ -155,6 +146,13 @@ public class FlatOptionPaneUI
 	protected Container createMessageArea() {
 		Container messageArea = super.createMessageArea();
 
+		// use non-UIResource OptionPane.messageAreaBorder to avoid that it is replaced when switching LaF
+		// and make panel non-opaque for OptionPane.background
+		updateAreaPanel( messageArea );
+
+		// make known sub-panels non-opaque for OptionPane.background
+		updateKnownChildPanels( messageArea );
+
 		// set icon-message gap
 		if( iconMessageGap > 0 ) {
 			Component iconMessageSeparator = SwingUtils.getComponentByName( messageArea, "OptionPane.separator" );
@@ -169,6 +167,10 @@ public class FlatOptionPaneUI
 	protected Container createButtonArea() {
 		Container buttonArea = super.createButtonArea();
 
+		// use non-UIResource OptionPane.buttonAreaBorder to avoid that it is replaced when switching LaF
+		// and make panel non-opaque for OptionPane.background
+		updateAreaPanel( buttonArea );
+
 		// scale button padding and subtract focusWidth
 		if( buttonArea.getLayout() instanceof ButtonAreaLayout ) {
 			ButtonAreaLayout layout = (ButtonAreaLayout) buttonArea.getLayout();
@@ -218,22 +220,33 @@ public class FlatOptionPaneUI
 		super.addMessageComponents( container, cons, msg, maxll, internallyCreated );
 	}
 
-	private void updateChildPanels( Container c ) {
-		for( Component child : c.getComponents() ) {
-			if( child.getClass() == JPanel.class ) {
-				JPanel panel = (JPanel)child;
+	private void updateAreaPanel( Container area ) {
+		if( !(area instanceof JPanel) )
+			return;
 
-				// make sub-panel non-opaque for OptionPane.background
+		// use non-UIResource border to avoid that it is replaced when switching LaF
+		// and make panel non-opaque for OptionPane.background
+		JPanel panel = (JPanel) area;
+		panel.setBorder( FlatUIUtils.nonUIResource( panel.getBorder() ) );
 		panel.setOpaque( false );
+	}
 
-				// use non-UIResource borders to avoid that they are replaced when switching LaF
-				Border border = panel.getBorder();
-				if( border instanceof UIResource )
-					panel.setBorder( FlatUIUtils.nonUIResource( border ) );
+	private void updateKnownChildPanels( Container c ) {
+		for( Component child : c.getComponents() ) {
+			if( child instanceof JPanel && child.getName() != null ) {
+				switch( child.getName() ) {
+					case "OptionPane.realBody":
+					case "OptionPane.body":
+					case "OptionPane.separator":
+					case "OptionPane.break":
+						// make known sub-panels non-opaque for OptionPane.background
+						((JPanel)child).setOpaque( false );
+						break;
+				}
 			}
 
 			if( child instanceof Container )
-				updateChildPanels( (Container) child );
+				updateKnownChildPanels( (Container) child );
 		}
 	}
 

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatPanelUI.java

@@ -16,6 +16,7 @@
 
 package com.formdev.flatlaf.ui;
 
+import java.awt.Dimension;
 import java.awt.Graphics;
 import java.awt.Graphics2D;
 import java.beans.PropertyChangeEvent;
@@ -23,6 +24,7 @@ import java.beans.PropertyChangeListener;
 import java.util.Map;
 import javax.swing.JComponent;
 import javax.swing.JPanel;
+import javax.swing.LookAndFeel;
 import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.basic.BasicPanelUI;
 import com.formdev.flatlaf.FlatClientProperties;
@@ -69,6 +71,8 @@ public class FlatPanelUI
 		super.installUI( c );
 
 		c.addPropertyChangeListener( this );
+		if( c.getClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER ) != null )
+			FullWindowContentSupport.registerPlaceholder( c );
 
 		installStyle( (JPanel) c );
 	}
@@ -78,10 +82,20 @@ public class FlatPanelUI
 		super.uninstallUI( c );
 
 		c.removePropertyChangeListener( this );
+		if( c.getClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER ) != null )
+			FullWindowContentSupport.unregisterPlaceholder( c );
 
 		oldStyleValues = null;
 	}
 
+	@Override
+	protected void installDefaults( JPanel p ) {
+		super.installDefaults( p );
+
+		if( p.getClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER ) != null )
+			LookAndFeel.installProperty( p, "opaque", false );
+	}
+
 	/** @since 2.0.1 */
 	@Override
 	public void propertyChange( PropertyChangeEvent e ) {
@@ -98,6 +112,17 @@ public class FlatPanelUI
 				c.revalidate();
 				c.repaint();
 				break;
+
+			case FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER:
+				JPanel p = (JPanel) e.getSource();
+				if( e.getOldValue() != null )
+					FullWindowContentSupport.unregisterPlaceholder( p );
+				if( e.getNewValue() != null )
+					FullWindowContentSupport.registerPlaceholder( p );
+
+				// make panel non-opaque for placeholders
+				LookAndFeel.installProperty( p, "opaque", e.getNewValue() == null );
+				break;
 		}
 	}
 
@@ -162,4 +187,19 @@ public class FlatPanelUI
 
 		paint( g, c );
 	}
+
+	@Override
+	public Dimension getPreferredSize( JComponent c ) {
+		Object value = c.getClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER );
+		if( value != null )
+			return FullWindowContentSupport.getPlaceholderPreferredSize( c, (String) value );
+
+		return super.getPreferredSize( c );
+	}
+
+	@Override
+	public void paint( Graphics g, JComponent c ) {
+		if( c.getClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER ) != null )
+			FullWindowContentSupport.debugPaint( g, c );
+	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatPopupFactory.java

@@ -36,6 +36,7 @@ import java.awt.Window;
 import java.awt.event.ComponentEvent;
 import java.awt.event.ComponentListener;
 import java.awt.event.MouseEvent;
+import java.awt.event.WindowFocusListener;
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
 import java.lang.invoke.MethodType;
@@ -70,6 +71,8 @@ import com.formdev.flatlaf.util.UIScale;
 public class FlatPopupFactory
 	extends PopupFactory
 {
+	static final String KEY_POPUP_USES_NATIVE_BORDER = "FlatLaf.internal.FlatPopupFactory.popupUsesNativeBorder";
+
 	private MethodHandle java8getPopupMethod;
 	private MethodHandle java9getPopupMethod;
 
@@ -83,23 +86,28 @@ public class FlatPopupFactory
 			y = pt.y;
 		}
 
+		fixLinuxWaylandJava21focusIssue( owner );
+
 		boolean forceHeavyWeight = isOptionEnabled( owner, contents, FlatClientProperties.POPUP_FORCE_HEAVY_WEIGHT, "Popup.forceHeavyWeight" );
 
 		if( !isOptionEnabled( owner, contents, FlatClientProperties.POPUP_DROP_SHADOW_PAINTED, "Popup.dropShadowPainted" ) || SystemInfo.isProjector || SystemInfo.isWebswing )
 			return new NonFlashingPopup( getPopupForScreenOfOwner( owner, contents, x, y, forceHeavyWeight ), contents );
 
 		// macOS and Linux adds drop shadow to heavy weight popups
-		if( SystemInfo.isMacOS || SystemInfo.isLinux )
-			return new NonFlashingPopup( getPopupForScreenOfOwner( owner, contents, x, y, true ), contents );
+		if( SystemInfo.isMacOS || SystemInfo.isLinux ) {
+			NonFlashingPopup popup = new NonFlashingPopup( getPopupForScreenOfOwner( owner, contents, x, y, true ), contents );
+			if( popup.popupWindow != null && SystemInfo.isMacOS && FlatNativeMacLibrary.isLoaded() )
+				setupRoundedBorder( popup.popupWindow, owner, contents );
+			return popup;
+		}
 
 		// Windows 11 with FlatLaf native library can use rounded corners and shows drop shadow for heavy weight popups
-		int borderCornerRadius;
 		if( isWindows11BorderSupported() &&
-			(borderCornerRadius = getBorderCornerRadius( owner, contents )) > 0 )
+			getBorderCornerRadius( owner, contents ) > 0 )
 		{
 			NonFlashingPopup popup = new NonFlashingPopup( getPopupForScreenOfOwner( owner, contents, x, y, true ), contents );
 			if( popup.popupWindow != null )
-				setupWindows11Border( popup.popupWindow, contents, borderCornerRadius );
+				setupRoundedBorder( popup.popupWindow, owner, contents );
 			return popup;
 		}
 
@@ -159,67 +167,6 @@ public class FlatPopupFactory
 		}
 	}
 
-	/**
-	 * Shows the given popup and, if necessary, fixes the location of a heavy weight popup window.
-	 * <p>
-	 * On a dual screen setup, where screens use different scale factors, it may happen
-	 * that the window location changes when showing a heavy weight popup window.
-	 * E.g. when opening a dialog on the secondary screen and making combobox popup visible.
-	 * <p>
-	 * This is a workaround for https://bugs.openjdk.java.net/browse/JDK-8224608
-	 */
-	private static void showPopupAndFixLocation( Popup popup, Window popupWindow ) {
-		if( popupWindow != null ) {
-			// remember location of heavy weight popup window
-			int x = popupWindow.getX();
-			int y = popupWindow.getY();
-
-			popup.show();
-
-			// restore popup window location if it has changed
-			// (probably scaled when screens use different scale factors)
-			if( popupWindow.getX() != x || popupWindow.getY() != y )
-				popupWindow.setLocation( x, y );
-		} else
-			popup.show();
-	}
-
-	private boolean isOptionEnabled( Component owner, Component contents, String clientKey, String uiKey ) {
-		Object value = getOption( owner, contents, clientKey, uiKey );
-		return (value instanceof Boolean) ? (Boolean) value : false;
-	}
-
-	private int getBorderCornerRadius( Component owner, Component contents ) {
-		String uiKey =
-			(contents instanceof BasicComboPopup) ? "ComboBox.borderCornerRadius" :
-			(contents instanceof JPopupMenu) ? "PopupMenu.borderCornerRadius" :
-			(contents instanceof JToolTip) ? "ToolTip.borderCornerRadius" :
-			"Popup.borderCornerRadius";
-
-		Object value = getOption( owner, contents, FlatClientProperties.POPUP_BORDER_CORNER_RADIUS, uiKey );
-		return (value instanceof Integer) ? (Integer) value : 0;
-	}
-
-	/**
-	 * Get option from:
-	 * <ol>
-	 * <li>client property {@code clientKey} of {@code owner}
-	 * <li>client property {@code clientKey} of {@code contents}
-	 * <li>UI property {@code uiKey}
-	 * </ol>
-	 */
-	private Object getOption( Component owner, Component contents, String clientKey, String uiKey ) {
-		for( Component c : new Component[] { owner, contents } ) {
-			if( c instanceof JComponent ) {
-				Object value = ((JComponent)c).getClientProperty( clientKey );
-				if( value != null )
-					return value;
-			}
-		}
-
-		return UIManager.get( uiKey );
-	}
-
 	/**
 	 * There is no API in Java 8 to force creation of heavy weight popups,
 	 * but it is possible with reflection. Java 9 provides a new method.
@@ -255,6 +202,33 @@ public class FlatPopupFactory
 		}
 	}
 
+	private static boolean isOptionEnabled( Component owner, Component contents, String clientKey, String uiKey ) {
+		Object value = getOption( owner, contents, clientKey, uiKey );
+		return (value instanceof Boolean) ? (Boolean) value : false;
+	}
+
+	/**
+	 * Get option from:
+	 * <ol>
+	 * <li>client property {@code clientKey} of {@code owner}
+	 * <li>client property {@code clientKey} of {@code contents}
+	 * <li>UI property {@code uiKey}
+	 * </ol>
+	 */
+	private static Object getOption( Component owner, Component contents, String clientKey, String uiKey ) {
+		for( Component c : new Component[] { owner, contents } ) {
+			if( c instanceof JComponent ) {
+				Object value = ((JComponent)c).getClientProperty( clientKey );
+				if( value != null )
+					return value;
+			}
+		}
+
+		return UIManager.get( uiKey );
+	}
+
+	//---- tooltips -----------------------------------------------------------
+
 	/**
 	 * Usually ToolTipManager places a tooltip at (mouseLocation.x, mouseLocation.y + 20).
 	 * In case that the tooltip would be partly outside of the screen,
@@ -339,16 +313,40 @@ public class FlatPopupFactory
 			((JComponent)owner).getToolTipLocation( me ) != null;
 	}
 
+	//---- native rounded border ----------------------------------------------
+
 	private static boolean isWindows11BorderSupported() {
 		return SystemInfo.isWindows_11_orLater && FlatNativeWindowsLibrary.isLoaded();
 	}
 
-	private static void setupWindows11Border( Window popupWindow, Component contents, int borderCornerRadius ) {
-		// make sure that the Windows 11 window is created
+	private static void setupRoundedBorder( Window popupWindow, Component owner, Component contents ) {
+		// make sure that the native window is created
 		if( !popupWindow.isDisplayable() )
 			popupWindow.addNotify();
 
-		// get window handle
+		int borderCornerRadius = getBorderCornerRadius( owner, contents );
+		float borderWidth = getRoundedBorderWidth( owner, contents );
+
+		// get Swing border color
+		Color borderColor = null; // use system default color
+		if( contents instanceof JComponent ) {
+			Border border = ((JComponent)contents).getBorder();
+			border = FlatUIUtils.unwrapNonUIResourceBorder( border );
+
+			// get color from border of contents (e.g. JPopupMenu or JToolTip)
+			if( border instanceof FlatLineBorder )
+				borderColor = ((FlatLineBorder)border).getLineColor();
+			else if( border instanceof LineBorder )
+				borderColor = ((LineBorder)border).getLineColor();
+			else if( border instanceof EmptyBorder )
+				borderColor = FlatNativeWindowsLibrary.COLOR_NONE; // do not paint border
+
+			// avoid that FlatLineBorder paints the Swing border
+			((JComponent)contents).putClientProperty( KEY_POPUP_USES_NATIVE_BORDER, true );
+		}
+
+		if( SystemInfo.isWindows ) {
+			// get native window handle
 			long hwnd = FlatNativeWindowsLibrary.getHWND( popupWindow );
 
 			// set corner preference
@@ -358,30 +356,16 @@ public class FlatPopupFactory
 			FlatNativeWindowsLibrary.setWindowCornerPreference( hwnd, cornerPreference );
 
 			// set border color
-		int red = -1; // use system default color
-		int green = 0;
-		int blue = 0;
-		if( contents instanceof JComponent ) {
-			Border border = ((JComponent)contents).getBorder();
-			border = FlatUIUtils.unwrapNonUIResourceBorder( border );
+			FlatNativeWindowsLibrary.dwmSetWindowAttributeCOLORREF( hwnd, FlatNativeWindowsLibrary.DWMWA_BORDER_COLOR, borderColor );
+		} else if( SystemInfo.isMacOS ) {
+			if( borderColor == null || borderColor == FlatNativeWindowsLibrary.COLOR_NONE )
+				borderWidth = 0;
 
-			// get color from border of contents (e.g. JPopupMenu or JToolTip)
-			Color borderColor = null;
-			if( border instanceof FlatLineBorder )
-				borderColor = ((FlatLineBorder)border).getLineColor();
-			else if( border instanceof LineBorder )
-				borderColor = ((LineBorder)border).getLineColor();
-			else if( border instanceof EmptyBorder )
-				red = -2; // do not paint border
-
-			if( borderColor != null ) {
-				red = borderColor.getRed();
-				green = borderColor.getGreen();
-				blue = borderColor.getBlue();
+			// set corner radius, border width and color
+			FlatNativeMacLibrary.setWindowRoundedBorder( popupWindow, borderCornerRadius,
+				borderWidth, (borderColor != null) ? borderColor.getRGB() : 0 );
 		}
 	}
-		FlatNativeWindowsLibrary.setWindowBorderColor( hwnd, red, green, blue );
-	}
 
 	private static void resetWindows11Border( Window popupWindow ) {
 		// get window handle
@@ -393,7 +377,34 @@ public class FlatPopupFactory
 		FlatNativeWindowsLibrary.setWindowCornerPreference( hwnd, FlatNativeWindowsLibrary.DWMWCP_DONOTROUND );
 	}
 
+	private static int getBorderCornerRadius( Component owner, Component contents ) {
+		String uiKey =
+			(contents instanceof BasicComboPopup) ? "ComboBox.borderCornerRadius" :
+			(contents instanceof JPopupMenu) ? "PopupMenu.borderCornerRadius" :
+			(contents instanceof JToolTip) ? "ToolTip.borderCornerRadius" :
+			"Popup.borderCornerRadius";
+
+		Object value = getOption( owner, contents, FlatClientProperties.POPUP_BORDER_CORNER_RADIUS, uiKey );
+		return (value instanceof Integer) ? (Integer) value : 0;
+	}
+
+	private static float getRoundedBorderWidth( Component owner, Component contents ) {
+		String uiKey =
+			(contents instanceof BasicComboPopup) ? "ComboBox.roundedBorderWidth" :
+			(contents instanceof JPopupMenu) ? "PopupMenu.roundedBorderWidth" :
+			(contents instanceof JToolTip) ? "ToolTip.roundedBorderWidth" :
+			"Popup.roundedBorderWidth";
+
+		Object value = getOption( owner, contents, FlatClientProperties.POPUP_ROUNDED_BORDER_WIDTH, uiKey );
+		return (value instanceof Number) ? ((Number)value).floatValue() : 0;
+	}
+
+	//---- fixes --------------------------------------------------------------
+
 	private static boolean overlapsHeavyWeightComponent( Component owner, Component contents, int x, int y ) {
+		if( owner == null )
+			return false;
+
 		Window window = SwingUtilities.getWindowAncestor( owner );
 		if( window == null )
 			return false;
@@ -420,6 +431,63 @@ public class FlatPopupFactory
 		return false;
 	}
 
+	/**
+	 * On Linux with Wayland, since Java 21, Swing adds a window focus listener to popup owner/invoker window,
+	 * which hides the popup as soon as the owner/invoker window looses focus.
+	 * This works fine for light-weight popups.
+	 * It also works for heavy-weight popups if they do not request focus.
+	 * Because FlatLaf always uses heavy-weight popups, all popups that request focus
+	 * are broken since Java 21.
+	 *
+	 * This method removes the problematic window focus listener.
+	 *
+	 * https://bugs.openjdk.org/browse/JDK-8280993
+	 * https://github.com/openjdk/jdk/pull/13830
+	 */
+	private static void fixLinuxWaylandJava21focusIssue( Component owner ) {
+		// only necessary on Linux when running in Java 21+
+		if( owner == null || !SystemInfo.isLinux || SystemInfo.javaVersion < SystemInfo.toVersion( 21, 0, 0, 0 ) )
+			return;
+
+		// get window
+		Window window = SwingUtilities.getWindowAncestor( owner );
+		if( window == null )
+			return;
+
+		// remove window focus listener, which was added from class sun.awt.UNIXToolkit since Java 21
+		for( WindowFocusListener l : window.getWindowFocusListeners() ) {
+			if( "sun.awt.UNIXToolkit$1".equals( l.getClass().getName() ) ) {
+				window.removeWindowFocusListener( l );
+				break;
+			}
+		}
+	}
+
+	/**
+	 * Shows the given popup and, if necessary, fixes the location of a heavy weight popup window.
+	 * <p>
+	 * On a dual screen setup, where screens use different scale factors, it may happen
+	 * that the window location changes when showing a heavy weight popup window.
+	 * E.g. when opening a dialog on the secondary screen and making combobox popup visible.
+	 * <p>
+	 * This is a workaround for https://bugs.openjdk.java.net/browse/JDK-8224608
+	 */
+	private static void showPopupAndFixLocation( Popup popup, Window popupWindow ) {
+		if( popupWindow != null ) {
+			// remember location of heavy weight popup window
+			int x = popupWindow.getX();
+			int y = popupWindow.getY();
+
+			popup.show();
+
+			// restore popup window location if it has changed
+			// (probably scaled when screens use different scale factors)
+			if( popupWindow.getX() != x || popupWindow.getY() != y )
+				popupWindow.setLocation( x, y );
+		} else
+			popup.show();
+	}
+
 	//---- class NonFlashingPopup ---------------------------------------------
 
 	private static class NonFlashingPopup
@@ -473,6 +541,9 @@ public class FlatPopupFactory
 
 		@Override
 		public void hide() {
+			if( contents instanceof JComponent )
+				((JComponent)contents).putClientProperty( KEY_POPUP_USES_NATIVE_BORDER, null );
+
 			if( delegate != null ) {
 				delegate.hide();
 				delegate = null;

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatRadioButtonUI.java

@@ -35,6 +35,7 @@ import javax.swing.CellRendererPane;
 import javax.swing.Icon;
 import javax.swing.JComponent;
 import javax.swing.LookAndFeel;
+import javax.swing.SwingConstants;
 import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
 import javax.swing.plaf.ComponentUI;
@@ -262,7 +263,7 @@ public class FlatRadioButtonUI
 
 	@Override
 	public void paint( Graphics g, JComponent c ) {
-		// fill background even if not opaque if
+		// fill background even if not opaque and if:
 		// - contentAreaFilled is true and
 		// - if background color is different to default background color
 		// (this paints selection if using the component as cell renderer)
@@ -278,20 +279,27 @@ public class FlatRadioButtonUI
 		int focusWidth = getIconFocusWidth( c );
 		if( focusWidth > 0 ) {
 			boolean ltr = c.getComponentOrientation().isLeftToRight();
+			int halign = ((AbstractButton)c).getHorizontalAlignment();
+			if( halign == SwingConstants.LEADING )
+				halign = ltr ? SwingConstants.LEFT : SwingConstants.RIGHT;
+			else if( halign == SwingConstants.TRAILING )
+				halign = ltr ? SwingConstants.RIGHT : SwingConstants.LEFT;
+
 			Insets insets = c.getInsets( tempInsets );
-			int leftOrRightInset = ltr ? insets.left : insets.right;
-			if( focusWidth > leftOrRightInset ) {
+			if( (focusWidth > insets.left || focusWidth > insets.right) &&
+				(halign == SwingConstants.LEFT || halign == SwingConstants.RIGHT) )
+			{
 				// The left (or right) inset is smaller than the focus width, which may be
 				// the case if insets were explicitly reduced (e.g. with an EmptyBorder).
 				// In this case the width has been increased in getPreferredSize() and
 				// here it is necessary to fix icon and text painting location.
-				int offset = focusWidth - leftOrRightInset;
-				if( !ltr )
-					offset = -offset;
+				int offset = (halign == SwingConstants.LEFT)
+					? Math.max( focusWidth - insets.left, 0 )
+					: -Math.max( focusWidth - insets.right, 0 );
 
 				// move the graphics origin to the left (or right)
 				g.translate( offset, 0 );
-				super.paint( g, c );
+				super.paint( FlatLabelUI.createGraphicsHTMLTextYCorrection( g, c ), c );
 				g.translate( -offset, 0 );
 				return;
 			}
@@ -328,6 +336,11 @@ public class FlatRadioButtonUI
 			: 0;
 	}
 
+	@Override
+	public int getBaseline( JComponent c, int width, int height ) {
+		return FlatButtonUI.getBaselineImpl( c, width, height );
+	}
+
 	//---- class FlatRadioButtonListener --------------------------------------
 
 	/** @since 2 */

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatRootPaneUI.java

@@ -28,8 +28,6 @@ import java.awt.Insets;
 import java.awt.LayoutManager;
 import java.awt.LayoutManager2;
 import java.awt.Window;
-import java.awt.event.ComponentAdapter;
-import java.awt.event.ComponentEvent;
 import java.awt.event.ComponentListener;
 import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
@@ -41,7 +39,6 @@ import javax.swing.JLayeredPane;
 import javax.swing.JMenuBar;
 import javax.swing.JRootPane;
 import javax.swing.LookAndFeel;
-import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
 import javax.swing.border.Border;
 import javax.swing.plaf.BorderUIResource;
@@ -88,8 +85,8 @@ public class FlatRootPaneUI
 
 	private Object nativeWindowBorderData;
 	private LayoutManager oldLayout;
-	private PropertyChangeListener ancestorListener;
-	private ComponentListener componentListener;
+	private ComponentListener macFullWindowContentListener;
+	private PropertyChangeListener macWindowBackgroundListener;
 
 	public static ComponentUI createUI( JComponent c ) {
 		return new FlatRootPaneUI();
@@ -107,6 +104,7 @@ public class FlatRootPaneUI
 			installBorder();
 
 		installNativeWindowBorder();
+		macInstallFullWindowContentSupport();
 	}
 
 	protected void installBorder() {
@@ -123,6 +121,7 @@ public class FlatRootPaneUI
 
 		uninstallNativeWindowBorder();
 		uninstallClientDecorations();
+		macUninstallFullWindowContentSupport();
 		rootPane = null;
 	}
 
@@ -157,9 +156,7 @@ public class FlatRootPaneUI
 				parent.setBackground( UIManager.getColor( "control" ) );
 		}
 
-		// enable dark window appearance on macOS when running in JetBrains Runtime
-		if( SystemInfo.isJetBrainsJVM && SystemInfo.isMacOS_10_14_Mojave_orLater )
-			c.putClientProperty( "jetbrains.awt.windowDarkAppearance", FlatLaf.isLafDark() );
+		macClearBackgroundForTranslucentWindow( c );
 	}
 
 	@Override
@@ -179,55 +176,20 @@ public class FlatRootPaneUI
 	protected void installListeners( JRootPane root ) {
 		super.installListeners( root );
 
-		if( SystemInfo.isJava_9_orLater ) {
-			// On HiDPI screens, where scaling is used, there may be white lines on the
-			// bottom and on the right side of the window when it is initially shown.
-			// This is very disturbing in dark themes, but hard to notice in light themes.
-			// Seems to be a rounding issue when Swing adds dirty region of window
-			// using RepaintManager.nativeAddDirtyRegion().
-			//
-			// Note: Not using a HierarchyListener here, which would be much easier,
-			// because this causes problems with mouse clicks in heavy-weight popups.
-			// Instead, add a listener to the root pane that waits until it is added
-			// to a window, then add a component listener to the window.
-			// See: https://github.com/JFormDesigner/FlatLaf/issues/371
-			ancestorListener = e -> {
-				Object oldValue = e.getOldValue();
-				Object newValue = e.getNewValue();
-				if( newValue instanceof Window ) {
-					if( componentListener == null ) {
-						componentListener = new ComponentAdapter() {
-							@Override
-							public void componentShown( ComponentEvent e ) {
-								// add whole root pane to dirty regions when window is initially shown
-								root.getParent().repaint( root.getX(), root.getY(), root.getWidth(), root.getHeight() );
-							}
-						};
-					}
-					((Window)newValue).addComponentListener( componentListener );
-				} else if( newValue == null && oldValue instanceof Window ) {
-					if( componentListener != null )
-						((Window)oldValue).removeComponentListener( componentListener );
-				}
-			};
-			root.addPropertyChangeListener( "ancestor", ancestorListener );
-		}
+		if( SystemInfo.isMacFullWindowContentSupported )
+			macFullWindowContentListener = FullWindowContentSupport.macInstallListeners( root );
+		macInstallWindowBackgroundListener( root );
 	}
 
 	@Override
 	protected void uninstallListeners( JRootPane root ) {
 		super.uninstallListeners( root );
 
-		if( SystemInfo.isJava_9_orLater ) {
-			if( componentListener != null ) {
-				Window window = SwingUtilities.windowForComponent( root );
-				if( window != null )
-					window.removeComponentListener( componentListener );
-				componentListener = null;
-			}
-			root.removePropertyChangeListener( "ancestor", ancestorListener );
-			ancestorListener = null;
+		if( SystemInfo.isMacFullWindowContentSupported ) {
+			FullWindowContentSupport.macUninstallListeners( root, macFullWindowContentListener );
+			macFullWindowContentListener = null;
 		}
+		macUninstallWindowBackgroundListener( root );
 	}
 
 	/** @since 1.1.2 */
@@ -307,19 +269,141 @@ public class FlatRootPaneUI
 
 	// layer title pane under frame content layer to allow placing menu bar over title pane
 	protected final static Integer TITLE_PANE_LAYER = JLayeredPane.FRAME_CONTENT_LAYER - 1;
+	private final static Integer TITLE_PANE_MOUSE_LAYER = JLayeredPane.FRAME_CONTENT_LAYER - 2;
+	private final static Integer WINDOW_TOP_BORDER_LAYER = Integer.MAX_VALUE;
+
+	// for fullWindowContent mode, layer title pane over frame content layer to allow placing title bar buttons over content
+	/** @since 3.4 */
+	protected final static Integer TITLE_PANE_FULL_WINDOW_CONTENT_LAYER = JLayeredPane.FRAME_CONTENT_LAYER + 1;
+
+	private Integer getLayerForTitlePane() {
+		return isFullWindowContent( rootPane ) ? TITLE_PANE_FULL_WINDOW_CONTENT_LAYER : TITLE_PANE_LAYER;
+	}
 
 	protected void setTitlePane( FlatTitlePane newTitlePane ) {
 		JLayeredPane layeredPane = rootPane.getLayeredPane();
 
-		if( titlePane != null )
+		if( titlePane != null ) {
 			layeredPane.remove( titlePane );
+			layeredPane.remove( titlePane.mouseLayer );
+			if( titlePane.windowTopBorderLayer != null )
+				layeredPane.remove( titlePane.windowTopBorderLayer );
+		}
 
-		if( newTitlePane != null )
-			layeredPane.add( newTitlePane, TITLE_PANE_LAYER );
+		if( newTitlePane != null ) {
+			layeredPane.add( newTitlePane, getLayerForTitlePane() );
+			layeredPane.add( newTitlePane.mouseLayer, TITLE_PANE_MOUSE_LAYER );
+			if( newTitlePane.windowTopBorderLayer != null && newTitlePane.isWindowTopBorderNeeded() && isFullWindowContent( rootPane ) )
+				layeredPane.add( newTitlePane.windowTopBorderLayer, WINDOW_TOP_BORDER_LAYER );
+		}
 
 		titlePane = newTitlePane;
 	}
 
+	private void macInstallFullWindowContentSupport() {
+		if( !SystemInfo.isMacOS )
+			return;
+
+		// set window buttons spacing
+		if( isMacButtonsSpacingSupported() && rootPane.isDisplayable() ) {
+			int buttonsSpacing = FlatNativeMacLibrary.BUTTONS_SPACING_DEFAULT;
+			String value = (String) rootPane.getClientProperty( FlatClientProperties.MACOS_WINDOW_BUTTONS_SPACING );
+			if( value != null ) {
+				switch( value ) {
+					case FlatClientProperties.MACOS_WINDOW_BUTTONS_SPACING_MEDIUM:
+						buttonsSpacing = FlatNativeMacLibrary.BUTTONS_SPACING_MEDIUM;
+						break;
+
+					case FlatClientProperties.MACOS_WINDOW_BUTTONS_SPACING_LARGE:
+						buttonsSpacing = FlatNativeMacLibrary.BUTTONS_SPACING_LARGE;
+						break;
+				}
+			}
+
+			FlatNativeMacLibrary.setWindowButtonsSpacing( getParentWindow( rootPane ), buttonsSpacing );
+		}
+
+		// update buttons bounds client property
+		FullWindowContentSupport.macUpdateFullWindowContentButtonsBoundsProperty( rootPane );
+	}
+
+	private void macUninstallFullWindowContentSupport() {
+		if( !SystemInfo.isMacOS )
+			return;
+
+		// do not uninstall when switching to another FlatLaf theme
+		if( UIManager.getLookAndFeel() instanceof FlatLaf )
+			return;
+
+		// reset window buttons spacing
+		if( isMacButtonsSpacingSupported() )
+			FlatNativeMacLibrary.setWindowButtonsSpacing( getParentWindow( rootPane ), FlatNativeMacLibrary.BUTTONS_SPACING_DEFAULT );
+
+		// remove buttons bounds client property
+		FullWindowContentSupport.macUninstallFullWindowContentButtonsBoundsProperty( rootPane );
+	}
+
+	private boolean isMacButtonsSpacingSupported() {
+		return SystemInfo.isMacOS && SystemInfo.isJava_17_orLater && FlatNativeMacLibrary.isLoaded();
+	}
+
+	private void macInstallWindowBackgroundListener( JRootPane c ) {
+		if( !SystemInfo.isMacOS )
+			return;
+
+		Window window = getParentWindow( c );
+		if( window != null && macWindowBackgroundListener == null ) {
+			macWindowBackgroundListener = e -> macClearBackgroundForTranslucentWindow( c );
+			window.addPropertyChangeListener( "background", macWindowBackgroundListener );
+		}
+	}
+
+	private void macUninstallWindowBackgroundListener( JRootPane c ) {
+		if( !SystemInfo.isMacOS )
+			return;
+
+		Window window = getParentWindow( c );
+		if( window != null && macWindowBackgroundListener != null ) {
+			window.removePropertyChangeListener( "background", macWindowBackgroundListener );
+			macWindowBackgroundListener = null;
+		}
+	}
+
+	/**
+	 * When setting window background to translucent color (alpha < 255),
+	 * Swing paints that window translucent on Windows and Linux, but not on macOS.
+	 * The reason for this is that FlatLaf sets the background color of the root pane,
+	 * and Swing behaves a bit differently on macOS than on other platforms in that case.
+	 * Other L&Fs do not set root pane background, which is {@code null} by default.
+	 * <p>
+	 * To fix this problem, set the root pane background to {@code null}
+	 * if windows uses a translucent background.
+	 */
+	private void macClearBackgroundForTranslucentWindow( JRootPane c ) {
+		if( !SystemInfo.isMacOS )
+			return;
+
+		Window window = getParentWindow( c );
+		if( window != null ) {
+			Color windowBackground = window.getBackground();
+			if( windowBackground != null &&
+				windowBackground.getAlpha() < 255 &&
+				c.getBackground() instanceof UIResource )
+			{
+				// clear root pane background
+				c.setBackground( null );
+			}
+		}
+	}
+
+	private Window getParentWindow( JRootPane c ) {
+		// not using SwingUtilities.windowForComponent() or SwingUtilities.getWindowAncestor()
+		// here because root panes may be nested and used anywhere (e.g. in JInternalFrame)
+		// but we're only interested in the "root" root pane, which is a direct child of the window
+		Container parent = c.getParent();
+		return (parent instanceof Window) ? (Window) parent : null;
+	}
+
 	@Override
 	public void propertyChange( PropertyChangeEvent e ) {
 		super.propertyChange( e );
@@ -364,6 +448,28 @@ public class FlatRootPaneUI
 					titlePane.titleBarColorsChanged();
 				break;
 
+			case FlatClientProperties.FULL_WINDOW_CONTENT:
+				if( titlePane != null ) {
+					rootPane.getLayeredPane().setLayer( titlePane, getLayerForTitlePane() );
+					if( titlePane.windowTopBorderLayer != null ) {
+						JLayeredPane layeredPane = rootPane.getLayeredPane();
+						if( titlePane.isWindowTopBorderNeeded() && isFullWindowContent( rootPane ) )
+							layeredPane.add( titlePane.windowTopBorderLayer, WINDOW_TOP_BORDER_LAYER );
+						else
+							layeredPane.remove( titlePane.windowTopBorderLayer );
+					}
+					titlePane.updateIcon();
+					titlePane.updateVisibility();
+					titlePane.updateFullWindowContentButtonsBoundsProperty();
+				}
+				FullWindowContentSupport.revalidatePlaceholders( rootPane );
+				rootPane.revalidate();
+				break;
+
+			case FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_BOUNDS:
+				FullWindowContentSupport.revalidatePlaceholders( rootPane );
+				break;
+
 			case FlatClientProperties.GLASS_PANE_FULL_HEIGHT:
 				rootPane.revalidate();
 				break;
@@ -372,14 +478,43 @@ public class FlatRootPaneUI
 				if( rootPane.isDisplayable() )
 					throw new IllegalComponentStateException( "The client property 'Window.style' must be set before the window becomes displayable." );
 				break;
+
+			case "ancestor":
+				if( e.getNewValue() instanceof Window )
+					macClearBackgroundForTranslucentWindow( rootPane );
+
+				macUninstallWindowBackgroundListener( rootPane );
+				macInstallWindowBackgroundListener( rootPane );
+
+				// FlatNativeMacLibrary.setWindowButtonsSpacing() and
+				// FullWindowContentSupport.macUpdateFullWindowContentButtonsBoundsProperty()
+				// require a native window, but setting the client properties
+				// "apple.awt.fullWindowContent" or FlatClientProperties.MACOS_WINDOW_BUTTONS_SPACING
+				// is usually done before the native window is created
+				// --> try again when native window is created
+				if( e.getNewValue() instanceof Window )
+					macInstallFullWindowContentSupport();
+				break;
+
+			case FlatClientProperties.MACOS_WINDOW_BUTTONS_SPACING:
+				macInstallFullWindowContentSupport();
+				break;
+
+			case "apple.awt.fullWindowContent":
+				if( SystemInfo.isMacFullWindowContentSupported )
+					FullWindowContentSupport.macUpdateFullWindowContentButtonsBoundsProperty( rootPane );
+				break;
 		}
 	}
 
+	/** @since 3.4 */
+	protected static boolean isFullWindowContent( JRootPane rootPane ) {
+		return FlatClientProperties.clientPropertyBoolean( rootPane, FlatClientProperties.FULL_WINDOW_CONTENT, false );
+	}
+
 	protected static boolean isMenuBarEmbedded( JRootPane rootPane ) {
-		RootPaneUI ui = rootPane.getUI();
-		return ui instanceof FlatRootPaneUI &&
-			((FlatRootPaneUI)ui).titlePane != null &&
-			((FlatRootPaneUI)ui).titlePane.isMenuBarEmbedded();
+		FlatTitlePane titlePane = getTitlePane( rootPane );
+		return titlePane != null && titlePane.isMenuBarEmbedded();
 	}
 
 	/** @since 2.4 */
@@ -415,24 +550,22 @@ public class FlatRootPaneUI
 		private Dimension computeLayoutSize( Container parent, Function<Component, Dimension> getSizeFunc ) {
 			JRootPane rootPane = (JRootPane) parent;
 
-			Dimension titlePaneSize = (titlePane != null)
-				? getSizeFunc.apply( titlePane )
-				: new Dimension();
 			Dimension contentSize = (rootPane.getContentPane() != null)
 				? getSizeFunc.apply( rootPane.getContentPane() )
-				: rootPane.getSize();
+				: rootPane.getSize(); // same as in JRootPane.RootLayout.preferredLayoutSize()
 
 			int width = contentSize.width; // title pane width is not considered here
-			int height = titlePaneSize.height + contentSize.height;
+			int height = contentSize.height;
+			if( titlePane != null && !isFullWindowContent( rootPane ) )
+				height += getSizeFunc.apply( titlePane ).height;
 			if( titlePane == null || !titlePane.isMenuBarEmbedded() ) {
 				JMenuBar menuBar = rootPane.getJMenuBar();
-				Dimension menuBarSize = (menuBar != null && menuBar.isVisible())
-					? getSizeFunc.apply( menuBar )
-					: new Dimension();
-
+				if( menuBar != null && menuBar.isVisible() ) {
+					Dimension menuBarSize = getSizeFunc.apply( menuBar );
 					width = Math.max( width, menuBarSize.width );
 					height += menuBarSize.height;
 				}
+			}
 
 			Insets insets = rootPane.getInsets();
 
@@ -456,11 +589,28 @@ public class FlatRootPaneUI
 			if( rootPane.getLayeredPane() != null )
 				rootPane.getLayeredPane().setBounds( x, y, width, height );
 
-			// title pane
+			// title pane (is a child of layered pane)
 			int nextY = 0;
 			if( titlePane != null ) {
 				int prefHeight = !isFullScreen ? titlePane.getPreferredSize().height : 0;
+				boolean isFullWindowContent = isFullWindowContent( rootPane );
+				if( isFullWindowContent && !UIManager.getBoolean( FlatTitlePane.KEY_DEBUG_SHOW_RECTANGLES ) ) {
+					// place title bar into top-right corner
+					int tw = Math.min( titlePane.getPreferredSize().width, width );
+					int tx = titlePane.getComponentOrientation().isLeftToRight() ? width - tw : 0;
+					titlePane.setBounds( tx, 0, tw, prefHeight );
+				} else
 					titlePane.setBounds( 0, 0, width, prefHeight );
+
+				titlePane.mouseLayer.setBounds( 0, 0, width, prefHeight );
+				if( titlePane.windowTopBorderLayer != null ) {
+					boolean show = isFullWindowContent && !titlePane.isWindowMaximized() && !isFullScreen;
+					if( show )
+						titlePane.windowTopBorderLayer.setBounds( 0, 0, width, 1 );
+					titlePane.windowTopBorderLayer.setVisible( show );
+				}
+
+				if( !isFullWindowContent )
 					nextY += prefHeight;
 			}
 
@@ -472,7 +622,7 @@ public class FlatRootPaneUI
 				rootPane.getGlassPane().setBounds( x, y + offset, width, height - offset );
 			}
 
-			// menu bar
+			// menu bar (is a child of layered pane)
 			JMenuBar menuBar = rootPane.getJMenuBar();
 			if( menuBar != null && menuBar.isVisible() ) {
 				boolean embedded = !isFullScreen && titlePane != null && titlePane.isMenuBarEmbedded();
@@ -480,13 +630,23 @@ public class FlatRootPaneUI
 					titlePane.validate();
 					menuBar.setBounds( titlePane.getMenuBarBounds() );
 				} else {
+					int mx = 0;
+					int mw = width;
+					if( titlePane != null && isFullWindowContent( rootPane ) ) {
+						// make menu bar width smaller to avoid that it overlaps title bar buttons
+						int tw = Math.min( titlePane.getPreferredSize().width, width );
+						mw -= tw;
+						if( !titlePane.getComponentOrientation().isLeftToRight() )
+							mx = tw;
+					}
+
 					Dimension prefSize = menuBar.getPreferredSize();
-					menuBar.setBounds( 0, nextY, width, prefSize.height );
+					menuBar.setBounds( mx, nextY, mw, prefSize.height );
 					nextY += prefSize.height;
 				}
 			}
 
-			// content pane
+			// content pane (is a child of layered pane)
 			Container contentPane = rootPane.getContentPane();
 			if( contentPane != null )
 				contentPane.setBounds( 0, nextY, width, Math.max( height - nextY, 0 ) );
@@ -499,7 +659,7 @@ public class FlatRootPaneUI
 		@Override
 		public void invalidateLayout( Container parent ) {
 			if( titlePane != null )
-				titlePane.menuBarChanged();
+				titlePane.menuBarInvalidate();
 		}
 
 		@Override

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatScrollBarUI.java

@@ -245,7 +245,7 @@ public class FlatScrollBarUI
 								// because scroll bars do not receive mouse exited event.
 								// The scroll pane, including its scroll bars, is not part
 								// of the component hierarchy and does not receive mouse events
-								// directly. Instead LWComponentPeer receives mouse events
+								// directly. Instead, LWComponentPeer receives mouse events
 								// and delegates them to peers, but entered/exited events
 								// are sent only for the whole scroll pane.
 								// Exited event is only sent when mouse leaves scroll pane.

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatScrollPaneBorder.java

@@ -0,0 +1,118 @@
+/*
+ * Copyright 2023 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.formdev.flatlaf.ui;
+
+import java.awt.Component;
+import java.awt.Insets;
+import javax.swing.JList;
+import javax.swing.JScrollPane;
+import javax.swing.JTable;
+import javax.swing.JTree;
+import javax.swing.UIManager;
+import javax.swing.text.JTextComponent;
+import com.formdev.flatlaf.ui.FlatStylingSupport.Styleable;
+import com.formdev.flatlaf.util.UIScale;
+
+/**
+ * Border for {@link javax.swing.JScrollPane}.
+ *
+ * @uiDefault ScrollPane.arc				int
+ * @uiDefault ScrollPane.List.arc			int
+ * @uiDefault ScrollPane.Table.arc			int
+ * @uiDefault ScrollPane.TextComponent.arc	int
+ * @uiDefault ScrollPane.Tree.arc			int
+
+ * @author Karl Tauber
+ * @since 3.3
+ */
+public class FlatScrollPaneBorder
+	extends FlatBorder
+{
+	@Styleable protected int arc = UIManager.getInt( "ScrollPane.arc" );
+
+	private boolean isArcStyled;
+	private final int listArc = FlatUIUtils.getUIInt( "ScrollPane.List.arc", -1 );
+	private final int tableArc = FlatUIUtils.getUIInt( "ScrollPane.Table.arc", -1 );
+	private final int textComponentArc = FlatUIUtils.getUIInt( "ScrollPane.TextComponent.arc", -1 );
+	private final int treeArc = FlatUIUtils.getUIInt( "ScrollPane.Tree.arc", -1 );
+
+	@Override
+	public Object applyStyleProperty( String key, Object value ) {
+		Object oldValue = super.applyStyleProperty( key, value );
+
+		if( "arc".equals( key ) )
+			isArcStyled = true;
+
+		return oldValue;
+	}
+
+	@Override
+	public Insets getBorderInsets( Component c, Insets insets ) {
+		insets = super.getBorderInsets( c, insets );
+
+		// if view is rounded, increase left and right insets to avoid that the viewport
+		// is painted over the rounded border on the corners
+		int padding = getLeftRightPadding( c );
+		if( padding > 0 ) {
+			insets.left += padding;
+			insets.right += padding;
+		}
+
+		return insets;
+	}
+
+	@Override
+	protected int getArc( Component c ) {
+		if( isCellEditor( c ) )
+			return 0;
+
+		if( isArcStyled )
+			return arc;
+
+		if( c instanceof JScrollPane ) {
+			Component view = FlatScrollPaneUI.getView( (JScrollPane) c );
+			if( listArc >= 0 && view instanceof JList )
+				return listArc;
+			if( tableArc >= 0 && view instanceof JTable )
+				return tableArc;
+			if( textComponentArc >= 0&& view instanceof JTextComponent )
+				return textComponentArc;
+			if( treeArc >= 0 && view instanceof JTree )
+				return treeArc;
+		}
+
+		return arc;
+	}
+
+	/**
+	 * Returns the scaled left/right padding used when arc is larger than zero.
+	 * <p>
+	 * This is the distance from the inside of the left border to the left side of the view component.
+	 * On the right side, this is the distance between the right side of the view component and
+	 * the vertical scrollbar. Or the inside of the right border if the scrollbar is hidden.
+	 */
+	public int getLeftRightPadding( Component c ) {
+		// Subtract lineWidth from radius because radius is given for the outside
+		// of the painted line, but insets from super already include lineWidth.
+		// Reduce padding by 10% to make padding slightly smaller because it is not recognizable
+		// when the view is minimally painted over the beginning of the border curve.
+		int arc = getArc( c );
+		return (arc > 0)
+			? Math.max( Math.round( UIScale.scale( ((arc / 2f) - getLineWidth( c )) * 0.9f ) ), 0 )
+			: 0;
+	}
+}

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatScrollPaneUI.java

@@ -17,9 +17,12 @@
 package com.formdev.flatlaf.ui;
 
 import java.awt.Component;
+import java.awt.Container;
 import java.awt.Graphics;
+import java.awt.Graphics2D;
 import java.awt.Insets;
 import java.awt.KeyboardFocusManager;
+import java.awt.LayoutManager;
 import java.awt.Rectangle;
 import java.awt.event.ContainerEvent;
 import java.awt.event.ContainerListener;
@@ -41,16 +44,19 @@ import javax.swing.JTree;
 import javax.swing.JViewport;
 import javax.swing.LookAndFeel;
 import javax.swing.ScrollPaneConstants;
+import javax.swing.ScrollPaneLayout;
 import javax.swing.Scrollable;
 import javax.swing.SwingConstants;
 import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
+import javax.swing.border.Border;
 import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.basic.BasicScrollPaneUI;
 import com.formdev.flatlaf.FlatClientProperties;
 import com.formdev.flatlaf.ui.FlatStylingSupport.Styleable;
 import com.formdev.flatlaf.ui.FlatStylingSupport.StyleableUI;
 import com.formdev.flatlaf.util.LoggingFacade;
+import com.formdev.flatlaf.util.UIScale;
 
 /**
  * Provides the Flat LaF UI delegate for {@link javax.swing.JScrollPane}.
@@ -97,7 +103,13 @@ public class FlatScrollPaneUI
 		super.installUI( c );
 
 		int focusWidth = UIManager.getInt( "Component.focusWidth" );
-		LookAndFeel.installProperty( c, "opaque", focusWidth == 0 );
+		int arc = UIManager.getInt( "ScrollPane.arc" );
+		LookAndFeel.installProperty( c, "opaque", focusWidth == 0 && arc == 0 );
+
+		// install layout manager
+		LayoutManager layout = c.getLayout();
+		if( layout != null && layout.getClass() == ScrollPaneLayout.UIResource.class )
+			c.setLayout( createScrollPaneLayout() );
 
 		installStyle();
 
@@ -108,6 +120,10 @@ public class FlatScrollPaneUI
 	public void uninstallUI( JComponent c ) {
 		MigLayoutVisualPadding.uninstall( scrollpane );
 
+		// uninstall layout manager
+		if( c.getLayout() instanceof FlatScrollPaneLayout )
+			c.setLayout( new ScrollPaneLayout.UIResource() );
+
 		super.uninstallUI( c );
 
 		oldStyleValues = null;
@@ -130,6 +146,13 @@ public class FlatScrollPaneUI
 		handler = null;
 	}
 
+	/**
+	 * @since 3.3
+	 */
+	protected FlatScrollPaneLayout createScrollPaneLayout() {
+		return new FlatScrollPaneLayout();
+	}
+
 	@Override
 	protected MouseWheelListener createMouseWheelListener() {
 		MouseWheelListener superListener = super.createMouseWheelListener();
@@ -290,8 +313,7 @@ public class FlatScrollPaneUI
 					Object corner = e.getNewValue();
 					if( corner instanceof JButton &&
 						((JButton)corner).getBorder() instanceof FlatButtonBorder &&
-						scrollpane.getViewport() != null &&
-						scrollpane.getViewport().getView() instanceof JTable )
+						getView( scrollpane ) instanceof JTable )
 					{
 						((JButton)corner).setBorder( BorderFactory.createEmptyBorder() );
 						((JButton)corner).setFocusable( false );
@@ -308,6 +330,18 @@ public class FlatScrollPaneUI
 					scrollpane.revalidate();
 					scrollpane.repaint();
 					break;
+
+				case "border":
+					Object newBorder = e.getNewValue();
+					if( newBorder != null && newBorder == UIManager.getBorder( "Table.scrollPaneBorder" ) ) {
+						// JTable.configureEnclosingScrollPaneUI() replaces the scrollpane border
+						// with another one --> re-apply style on new border
+						borderShared = null;
+						installStyle();
+						scrollpane.revalidate();
+						scrollpane.repaint();
+					}
+					break;
 			}
 		};
 	}
@@ -334,9 +368,10 @@ public class FlatScrollPaneUI
 
 	/** @since 2 */
 	protected Object applyStyleProperty( String key, Object value ) {
-		if( key.equals( "focusWidth" ) ) {
+		if( key.equals( "focusWidth" ) || key.equals( "arc" ) ) {
 			int focusWidth = (value instanceof Integer) ? (int) value : UIManager.getInt( "Component.focusWidth" );
-			LookAndFeel.installProperty( scrollpane, "opaque", focusWidth == 0 );
+			int arc = (value instanceof Integer) ? (int) value : UIManager.getInt( "ScrollPane.arc" );
+			LookAndFeel.installProperty( scrollpane, "opaque", focusWidth == 0 && arc == 0 );
 		}
 
 		if( borderShared == null )
@@ -402,13 +437,46 @@ public class FlatScrollPaneUI
 				c.getHeight() - insets.top - insets.bottom );
 		}
 
+		// if view is rounded, paint rounded background with view background color
+		// to ensure that free areas at left and right have same color as view
+		Component view;
+		float arc = getBorderArc( scrollpane );
+		if( arc > 0 && (view = getView( scrollpane )) != null ) {
+			float focusWidth = FlatUIUtils.getBorderFocusWidth( c );
+
+			g.setColor( view.getBackground() );
+
+			Object[] oldRenderingHints = FlatUIUtils.setRenderingHints( g );
+			FlatUIUtils.paintComponentBackground( (Graphics2D) g, 0, 0, c.getWidth(), c.getHeight(), focusWidth, arc );
+			FlatUIUtils.resetRenderingHints( g, oldRenderingHints );
+		}
+
 		paint( g, c );
 	}
 
+	@Override
+	public void paint( Graphics g, JComponent c ) {
+		Border viewportBorder = scrollpane.getViewportBorder();
+		if( viewportBorder != null ) {
+			Rectangle r = scrollpane.getViewportBorderBounds();
+			int padding = getBorderLeftRightPadding( scrollpane );
+			JScrollBar vsb = scrollpane.getVerticalScrollBar();
+			if( padding > 0 &&
+				vsb != null && vsb.isVisible() &&
+				scrollpane.getLayout() instanceof FlatScrollPaneLayout &&
+				((FlatScrollPaneLayout)scrollpane.getLayout()).canIncreaseViewportWidth( scrollpane ) )
+			{
+				boolean ltr = scrollpane.getComponentOrientation().isLeftToRight();
+				int extraWidth = Math.min( padding, vsb.getWidth() );
+				viewportBorder.paintBorder( scrollpane, g, r.x - (ltr ? 0 : extraWidth), r.y, r.width + extraWidth, r.height );
+			} else
+				viewportBorder.paintBorder( scrollpane, g, r.x, r.y, r.width, r.height );
+		}
+	}
+
 	/** @since 1.3 */
 	public static boolean isPermanentFocusOwner( JScrollPane scrollPane ) {
-		JViewport viewport = scrollPane.getViewport();
-		Component view = (viewport != null) ? viewport.getView() : null;
+		Component view = getView( scrollPane );
 		if( view == null )
 			return false;
 
@@ -428,6 +496,25 @@ public class FlatScrollPaneUI
 		return false;
 	}
 
+	static Component getView( JScrollPane scrollPane ) {
+		JViewport viewport = scrollPane.getViewport();
+		return (viewport != null) ? viewport.getView() : null;
+	}
+
+	private static float getBorderArc( JScrollPane scrollPane ) {
+		Border border = scrollPane.getBorder();
+		return (border instanceof FlatScrollPaneBorder)
+			? UIScale.scale( (float) ((FlatScrollPaneBorder)border).getArc( scrollPane ) )
+			: 0;
+	}
+
+	private static int getBorderLeftRightPadding( JScrollPane scrollPane ) {
+		Border border = scrollPane.getBorder();
+		return (border instanceof FlatScrollPaneBorder)
+			? ((FlatScrollPaneBorder)border).getLeftRightPadding( scrollPane )
+			: 0;
+	}
+
 	//---- class Handler ------------------------------------------------------
 
 	/**
@@ -450,13 +537,71 @@ public class FlatScrollPaneUI
 		@Override
 		public void focusGained( FocusEvent e ) {
 			// necessary to update focus border
+			if( scrollpane.getBorder() instanceof FlatBorder )
 				scrollpane.repaint();
 		}
 
 		@Override
 		public void focusLost( FocusEvent e ) {
 			// necessary to update focus border
+			if( scrollpane.getBorder() instanceof FlatBorder )
 				scrollpane.repaint();
 		}
 	}
+
+	//---- class FlatScrollPaneLayout -----------------------------------------
+
+	/**
+	 * @since 3.3
+	 */
+	protected static class FlatScrollPaneLayout
+		extends ScrollPaneLayout.UIResource
+	{
+		@Override
+		public void layoutContainer( Container parent ) {
+			super.layoutContainer( parent );
+
+			JScrollPane scrollPane = (JScrollPane) parent;
+			int padding = getBorderLeftRightPadding( scrollPane );
+			if( padding > 0 && vsb != null && vsb.isVisible() ) {
+				// move vertical scrollbar to trailing edge
+				Insets insets = scrollPane.getInsets();
+				Rectangle r = vsb.getBounds();
+				int y = Math.max( r.y, insets.top + padding );
+				int y2 = Math.min( r.y + r.height, scrollPane.getHeight() - insets.bottom - padding );
+				boolean ltr = scrollPane.getComponentOrientation().isLeftToRight();
+
+				vsb.setBounds( r.x + (ltr ? padding : -padding), y, r.width, y2 - y );
+
+				// increase width of viewport, column header and horizontal scrollbar
+				if( canIncreaseViewportWidth( scrollPane ) ) {
+					int extraWidth = Math.min( padding, vsb.getWidth() );
+					resizeViewport( viewport, extraWidth, ltr );
+					resizeViewport( colHead, extraWidth, ltr );
+					resizeViewport( hsb, extraWidth, ltr );
+				}
+			}
+		}
+
+		boolean canIncreaseViewportWidth( JScrollPane scrollPane ) {
+			return scrollPane.getComponentOrientation().isLeftToRight()
+				? !isCornerVisible( upperRight ) && !isCornerVisible( lowerRight )
+				: !isCornerVisible( upperLeft ) && !isCornerVisible( lowerLeft );
+		}
+
+		private static boolean isCornerVisible( Component corner ) {
+			return corner != null &&
+				corner.getWidth() > 0 &&
+				corner.getHeight() > 0 &&
+				corner.isVisible();
+		}
+
+		private static void resizeViewport( Component c, int extraWidth, boolean ltr ) {
+			if( c == null )
+				return;
+
+			Rectangle vr = c.getBounds();
+			c.setBounds( vr.x - (ltr ? 0 : extraWidth), vr.y, vr.width + extraWidth, vr.height );
+		}
+	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatSplitPaneUI.java

@@ -16,7 +16,9 @@
 
 package com.formdev.flatlaf.ui;
 
+import java.awt.Canvas;
 import java.awt.Color;
+import java.awt.Component;
 import java.awt.Container;
 import java.awt.Cursor;
 import java.awt.Graphics;
@@ -67,6 +69,8 @@ import com.formdev.flatlaf.util.UIScale;
  * <!-- FlatSplitPaneUI -->
  *
  * @uiDefault Component.arrowType						String	chevron (default) or triangle
+ * @uiDefault SplitPaneDivider.hoverColor				Color	optional
+ * @uiDefault SplitPaneDivider.pressedColor				Color	optional
  * @uiDefault SplitPaneDivider.oneTouchArrowColor		Color
  * @uiDefault SplitPaneDivider.oneTouchHoverArrowColor	Color
  * @uiDefault SplitPaneDivider.oneTouchPressedArrowColor Color
@@ -80,9 +84,10 @@ import com.formdev.flatlaf.util.UIScale;
  */
 public class FlatSplitPaneUI
 	extends BasicSplitPaneUI
-	implements StyleableUI
+	implements StyleableUI, FlatTitlePane.TitleBarCaptionHitTest
 {
 	@Styleable protected String arrowType;
+	/** @since 3.3 */ @Styleable protected Color draggingColor;
 	@Styleable protected Color oneTouchArrowColor;
 	@Styleable protected Color oneTouchHoverArrowColor;
 	@Styleable protected Color oneTouchPressedArrowColor;
@@ -104,6 +109,8 @@ public class FlatSplitPaneUI
 	protected void installDefaults() {
 		arrowType = UIManager.getString( "Component.arrowType" );
 
+		draggingColor = UIManager.getColor( "SplitPaneDivider.draggingColor" );
+
 		// get one-touch colors before invoking super.installDefaults() because they are
 		// used in there on LaF switching
 		oneTouchArrowColor = UIManager.getColor( "SplitPaneDivider.oneTouchArrowColor" );
@@ -117,6 +124,8 @@ public class FlatSplitPaneUI
 	protected void uninstallDefaults() {
 		super.uninstallDefaults();
 
+		draggingColor = null;
+
 		oneTouchArrowColor = null;
 		oneTouchHoverArrowColor = null;
 		oneTouchPressedArrowColor = null;
@@ -183,12 +192,58 @@ public class FlatSplitPaneUI
 		return FlatStylingSupport.getAnnotatedStyleableValue( this, key );
 	}
 
+	@Override
+	protected Component createDefaultNonContinuousLayoutDivider() {
+		// only used for non-continuous layout if left or right component is heavy weight
+		return new Canvas() {
+			@Override
+			public void paint( Graphics g ) {
+				if( !isContinuousLayout() && getLastDragLocation() != -1 )
+					paintDragDivider( g, 0 );
+			}
+		};
+	}
+
+	@Override
+	public void finishedPaintingChildren( JSplitPane sp, Graphics g ) {
+		if( sp == splitPane && getLastDragLocation() != -1 && !isContinuousLayout() && !draggingHW )
+			paintDragDivider( g, getLastDragLocation() );
+	}
+
+	private void paintDragDivider( Graphics g, int dividerLocation ) {
+		// divider bounds
+		boolean horizontal = (getOrientation() == JSplitPane.HORIZONTAL_SPLIT);
+		int x = horizontal ? dividerLocation : 0;
+		int y = !horizontal ? dividerLocation : 0;
+		int width = horizontal ? dividerSize : splitPane.getWidth();
+		int height = !horizontal ? dividerSize : splitPane.getHeight();
+
+		// paint background
+		g.setColor( FlatUIUtils.deriveColor( draggingColor, splitPane.getBackground() ) );
+		g.fillRect( x, y, width, height );
+
+		// paint divider style (e.g. grip)
+		if( divider instanceof FlatSplitPaneDivider )
+			((FlatSplitPaneDivider)divider).paintStyle( g, x, y, width, height );
+	}
+
+	//---- interface FlatTitlePane.TitleBarCaptionHitTest ----
+
+	/** @since 3.4 */
+	@Override
+	public Boolean isTitleBarCaptionAt( int x, int y ) {
+		// necessary because BasicSplitPaneDivider adds some mouse listeners for dragging divider
+		return null; // check children
+	}
+
 	//---- class FlatSplitPaneDivider -----------------------------------------
 
 	protected class FlatSplitPaneDivider
 		extends BasicSplitPaneDivider
 	{
 		@Styleable protected String style = UIManager.getString( "SplitPaneDivider.style" );
+		/** @since 3.3 */ @Styleable protected Color hoverColor = UIManager.getColor( "SplitPaneDivider.hoverColor" );
+		/** @since 3.3 */ @Styleable protected Color pressedColor = UIManager.getColor( "SplitPaneDivider.pressedColor" );
 		@Styleable protected Color gripColor = UIManager.getColor( "SplitPaneDivider.gripColor" );
 		@Styleable protected int gripDotCount = FlatUIUtils.getUIInt( "SplitPaneDivider.gripDotCount", 3 );
 		@Styleable protected int gripDotSize = FlatUIUtils.getUIInt( "SplitPaneDivider.gripDotSize", 3 );
@@ -246,20 +301,40 @@ public class FlatSplitPaneUI
 					// necessary to show/hide one-touch buttons on expand/collapse
 					doLayout();
 					break;
+
+				case FlatClientProperties.SPLIT_PANE_EXPANDABLE_SIDE:
+					revalidate();
+					break;
 			}
 		}
 
 		@Override
 		public void paint( Graphics g ) {
+			// paint hover or pressed background
+			Color hoverOrPressedColor = (isContinuousLayout() && dragger != null)
+				? pressedColor
+				: (isMouseOver() && dragger == null
+					? hoverColor
+					: null);
+			if( hoverOrPressedColor != null ) {
+				g.setColor( FlatUIUtils.deriveColor( hoverOrPressedColor, splitPane.getBackground() ) );
+				g.fillRect( 0, 0, getWidth(), getHeight() );
+			}
+
 			super.paint( g );
 
+			paintStyle( g, 0, 0, getWidth(), getHeight() );
+		}
+
+		/** @since 3.3 */
+		protected void paintStyle( Graphics g, int x, int y, int width, int height ) {
 			if( "plain".equals( style ) )
 				return;
 
 			Object[] oldRenderingHints = FlatUIUtils.setRenderingHints( g );
 
 			g.setColor( gripColor );
-			paintGrip( g, 0, 0, getWidth(), getHeight() );
+			paintGrip( g, x, y, width, height );
 
 			FlatUIUtils.resetRenderingHints( g, oldRenderingHints );
 		}
@@ -286,6 +361,29 @@ public class FlatSplitPaneUI
 				: location == (splitPane.getWidth() - getWidth() - insets.right);
 		}
 
+		@Override
+		protected void setMouseOver( boolean mouseOver ) {
+			super.setMouseOver( mouseOver );
+			repaintIfNecessary();
+		}
+
+		@Override
+		protected void prepareForDragging() {
+			super.prepareForDragging();
+			repaintIfNecessary();
+		}
+
+		@Override
+		protected void finishDraggingTo( int location ) {
+			super.finishDraggingTo( location );
+			repaintIfNecessary();
+		}
+
+		private void repaintIfNecessary() {
+			if( hoverColor != null || pressedColor != null )
+				repaint();
+		}
+
 		//---- class FlatOneTouchButton ---------------------------------------
 
 		protected class FlatOneTouchButton

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatTableHeaderUI.java

@@ -18,6 +18,7 @@ package com.formdev.flatlaf.ui;
 
 import java.awt.Color;
 import java.awt.Component;
+import java.awt.Container;
 import java.awt.Cursor;
 import java.awt.Dimension;
 import java.awt.Graphics;
@@ -28,16 +29,15 @@ import java.awt.event.MouseEvent;
 import java.awt.geom.Rectangle2D;
 import java.beans.PropertyChangeListener;
 import java.util.Map;
+import javax.swing.CellRendererPane;
 import javax.swing.Icon;
 import javax.swing.JComponent;
 import javax.swing.JLabel;
 import javax.swing.JTable;
 import javax.swing.SwingConstants;
 import javax.swing.UIManager;
-import javax.swing.border.Border;
 import javax.swing.event.MouseInputListener;
 import javax.swing.plaf.ComponentUI;
-import javax.swing.plaf.UIResource;
 import javax.swing.plaf.basic.BasicTableHeaderUI;
 import javax.swing.table.JTableHeader;
 import javax.swing.table.TableCellRenderer;
@@ -114,6 +114,11 @@ public class FlatTableHeaderUI
 	public void installUI( JComponent c ) {
 		super.installUI( c );
 
+		// replace cell renderer pane
+		header.remove( rendererPane );
+		rendererPane = new FlatTableHeaderCellRendererPane();
+		header.add( rendererPane );
+
 		installStyle();
 	}
 
@@ -265,16 +270,8 @@ public class FlatTableHeaderUI
 			}
 		}
 
-		// temporary use own default renderer
-		FlatTableCellHeaderRenderer tempRenderer = new FlatTableCellHeaderRenderer( header.getDefaultRenderer() );
-		header.setDefaultRenderer( tempRenderer );
-
 		// paint header
 		super.paint( g, c );
-
-		// restore default renderer
-		tempRenderer.reset();
-		header.setDefaultRenderer( tempRenderer.delegate );
 	}
 
 	private boolean isSystemDefaultRenderer( Object headerRenderer ) {
@@ -332,119 +329,129 @@ public class FlatTableHeaderUI
 		return false;
 	}
 
-	//---- class FlatTableCellHeaderRenderer ----------------------------------
+	//---- class FlatTableHeaderCellRendererPane ------------------------------
 
 	/**
-	 * A delegating header renderer that is only used to paint hover and pressed
-	 * background/foreground and to paint sort arrows at top, bottom or left position.
+	 * Cell renderer pane that is used to paint hover and pressed background/foreground
+	 * and to paint sort arrows at top, bottom or left position.
 	 */
-	private class FlatTableCellHeaderRenderer
-		implements TableCellRenderer, Border, UIResource
+	private class FlatTableHeaderCellRendererPane
+		extends CellRendererPane
 	{
-		private final TableCellRenderer delegate;
+		private final Icon ascendingSortIcon;
+		private final Icon descendingSortIcon;
 
-		private JLabel l;
-		private Color oldBackground;
-		private Color oldForeground;
-		private Boolean oldOpaque;
-		private int oldHorizontalTextPosition = -1;
-		private Border origBorder;
-		private Icon sortIcon;
-
-		FlatTableCellHeaderRenderer( TableCellRenderer delegate ) {
-			this.delegate = delegate;
+		public FlatTableHeaderCellRendererPane() {
+			ascendingSortIcon = UIManager.getIcon( "Table.ascendingSortIcon" );
+			descendingSortIcon = UIManager.getIcon( "Table.descendingSortIcon" );
 		}
 
 		@Override
-		public Component getTableCellRendererComponent( JTable table, Object value, boolean isSelected,
-			boolean hasFocus, int row, int column )
-		{
-			Component c = delegate.getTableCellRendererComponent( table, value, isSelected, hasFocus, row, column );
-			if( !(c instanceof JLabel) )
-				return c;
+		public void paintComponent( Graphics g, Component c, Container p, int x, int y, int w, int h, boolean shouldValidate ) {
+			if( !(c instanceof JLabel) ) {
+				super.paintComponent( g, c, p, x, y, w, h, shouldValidate );
+				return;
+			}
 
-			l = (JLabel) c;
+			JLabel l = (JLabel) c;
+			Color oldBackground = null;
+			Color oldForeground = null;
+			boolean oldOpaque = false;
+			Icon oldIcon = null;
+			int oldHorizontalTextPosition = -1;
 
 			// hover and pressed background/foreground
 			TableColumn draggedColumn = header.getDraggedColumn();
 			Color background = null;
 			Color foreground = null;
-			if( draggedColumn != null && header.getTable().convertColumnIndexToView( draggedColumn.getModelIndex() ) == column ) {
+			if( draggedColumn != null &&
+				header.getTable().convertColumnIndexToView( draggedColumn.getModelIndex() )
+					== getColumn( x - header.getDraggedDistance(), w ) )
+			{
 				background = pressedBackground;
 				foreground = pressedForeground;
-			} else if( getRolloverColumn() == column ) {
+			} else if( getRolloverColumn() >= 0 && getRolloverColumn() == getColumn( x, w ) ) {
 				background = hoverBackground;
 				foreground = hoverForeground;
 			}
 			if( background != null ) {
-				if( oldBackground == null )
 				oldBackground = l.getBackground();
-				if( oldOpaque == null )
 				oldOpaque = l.isOpaque();
 				l.setBackground( FlatUIUtils.deriveColor( background, header.getBackground() ) );
 				l.setOpaque( true );
 			}
 			if( foreground != null ) {
-				if( oldForeground == null )
 				oldForeground = l.getForeground();
 				l.setForeground( FlatUIUtils.deriveColor( foreground, header.getForeground() ) );
 			}
 
-			// sort icon
+			// sort icon position
+			Icon icon = l.getIcon();
+			boolean isSortIcon = (icon != null && (icon == ascendingSortIcon || icon == descendingSortIcon));
+			if( isSortIcon ) {
 				if( sortIconPosition == SwingConstants.LEFT ) {
 					// left
-				if( oldHorizontalTextPosition < 0 )
 					oldHorizontalTextPosition = l.getHorizontalTextPosition();
 					l.setHorizontalTextPosition( SwingConstants.RIGHT );
 				} else if( sortIconPosition == SwingConstants.TOP || sortIconPosition == SwingConstants.BOTTOM ) {
 					// top or bottom
-				sortIcon = l.getIcon();
-				origBorder = l.getBorder();
+					oldIcon = icon;
 					l.setIcon( null );
-				l.setBorder( this );
+				}
 			}
 
-			return l;
+			// paint renderer component
+			super.paintComponent( g, c, p, x, y, w, h, shouldValidate );
+
+			// paint top or bottom sort icon
+			if( isSortIcon && (sortIconPosition == SwingConstants.TOP || sortIconPosition == SwingConstants.BOTTOM) ) {
+				int xi = x + ((w - icon.getIconWidth()) / 2);
+				int yi = (sortIconPosition == SwingConstants.TOP)
+					? y + UIScale.scale( 1 )
+					: y + height - icon.getIconHeight()
+						- 1 // for gap
+						- (int) (1 * UIScale.getUserScaleFactor()); // for bottom border
+				icon.paintIcon( c, g, xi, yi );
 			}
 
-		void reset() {
-			if( l == null )
-				return;
-
-			if( oldBackground != null )
+			// restore modified renderer component properties
+			if( background != null ) {
 				l.setBackground( oldBackground );
-			if( oldForeground != null )
-				l.setForeground( oldForeground );
-			if( oldOpaque != null )
 				l.setOpaque( oldOpaque );
+			}
+			if( foreground != null )
+				l.setForeground( oldForeground );
+			if( oldIcon != null )
+				l.setIcon( oldIcon );
 			if( oldHorizontalTextPosition >= 0 )
 				l.setHorizontalTextPosition( oldHorizontalTextPosition );
 		}
 
-		@Override
-		public void paintBorder( Component c, Graphics g, int x, int y, int width, int height ) {
-			if( origBorder != null )
-				origBorder.paintBorder( c, g, x, y, width, height );
+		/**
+		 * Get column index for given coordinates.
+		 */
+		private int getColumn( int x, int width ) {
+			TableColumnModel columnModel = header.getColumnModel();
+			int columnCount = columnModel.getColumnCount();
+			boolean ltr = header.getComponentOrientation().isLeftToRight();
+			int cx = ltr ? 0 : getWidthInRightToLef();
 
-			if( sortIcon != null ) {
-				int xi = x + ((width - sortIcon.getIconWidth()) / 2);
-				int yi = (sortIconPosition == SwingConstants.TOP)
-					? y + UIScale.scale( 1 )
-					: y + height - sortIcon.getIconHeight()
-						- 1 // for gap
-						- (int) (1 * UIScale.getUserScaleFactor()); // for bottom border
-				sortIcon.paintIcon( c, g, xi, yi );
+			for( int i = 0; i < columnCount; i++ ) {
+				int cw = columnModel.getColumn( i ).getWidth();
+				if( x == cx - (ltr ? 0 : cw) && width == cw )
+					return i;
+
+				cx += ltr ? cw : -cw;
 			}
+			return -1;
 		}
 
-		@Override
-		public Insets getBorderInsets( Component c ) {
-			return (origBorder != null) ? origBorder.getBorderInsets( c ) : new Insets( 0, 0, 0, 0 );
-		}
-
-		@Override
-		public boolean isBorderOpaque() {
-			return (origBorder != null) ? origBorder.isBorderOpaque() : false;
+		// similar to JTableHeader.getWidthInRightToLeft()
+		private int getWidthInRightToLef() {
+			JTable table = header.getTable();
+			return (table != null && table.getAutoResizeMode() != JTable.AUTO_RESIZE_OFF)
+				? table.getWidth()
+				: header.getWidth();
 		}
 	}
 

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatTableUI.java

@@ -17,27 +17,39 @@
 package com.formdev.flatlaf.ui;
 
 import java.awt.Color;
+import java.awt.Component;
 import java.awt.Container;
 import java.awt.Dimension;
 import java.awt.EventQueue;
 import java.awt.Graphics;
 import java.awt.Graphics2D;
 import java.awt.Insets;
+import java.awt.event.ActionEvent;
 import java.awt.event.FocusEvent;
 import java.awt.event.FocusListener;
 import java.awt.geom.Rectangle2D;
+import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
 import java.util.Map;
+import javax.swing.Action;
+import javax.swing.ActionMap;
 import javax.swing.JComponent;
 import javax.swing.JScrollPane;
+import javax.swing.JTable;
+import javax.swing.JTextField;
 import javax.swing.JViewport;
 import javax.swing.LookAndFeel;
+import javax.swing.SwingConstants;
 import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
 import javax.swing.plaf.ComponentUI;
+import javax.swing.plaf.UIResource;
 import javax.swing.plaf.basic.BasicTableUI;
+import javax.swing.table.DefaultTableCellRenderer;
 import javax.swing.table.JTableHeader;
+import javax.swing.table.TableCellRenderer;
 import com.formdev.flatlaf.FlatClientProperties;
+import com.formdev.flatlaf.icons.FlatCheckBoxIcon;
 import com.formdev.flatlaf.ui.FlatStylingSupport.Styleable;
 import com.formdev.flatlaf.ui.FlatStylingSupport.StyleableUI;
 import com.formdev.flatlaf.util.Graphics2DProxy;
@@ -81,6 +93,7 @@ import com.formdev.flatlaf.util.UIScale;
  * @uiDefault Table.selectionInactiveBackground			Color
  * @uiDefault Table.selectionInactiveForeground			Color
  * @uiDefault Table.paintOutsideAlternateRows			boolean
+ * @uiDefault Table.editorSelectAllOnStartEditing		boolean
  *
  * <!-- FlatTableCellBorder -->
  *
@@ -116,6 +129,7 @@ public class FlatTableUI
 	private boolean oldShowHorizontalLines;
 	private boolean oldShowVerticalLines;
 	private Dimension oldIntercellSpacing;
+	private TableCellRenderer oldBooleanRenderer;
 
 	private PropertyChangeListener propertyChangeListener;
 	private Map<String, Object> oldStyleValues;
@@ -151,19 +165,35 @@ public class FlatTableUI
 		if( rowHeight > 0 )
 			LookAndFeel.installProperty( table, "rowHeight", UIScale.scale( rowHeight ) );
 
-		if( !showHorizontalLines ) {
+		FlatTablePropertyWatcher watcher = FlatTablePropertyWatcher.get( table );
+		if( watcher != null )
+			watcher.enabled = false;
+
+		if( !showHorizontalLines && (watcher == null || !watcher.showHorizontalLinesChanged) ) {
 			oldShowHorizontalLines = table.getShowHorizontalLines();
 			table.setShowHorizontalLines( false );
 		}
-		if( !showVerticalLines ) {
+		if( !showVerticalLines && (watcher == null || !watcher.showVerticalLinesChanged) ) {
 			oldShowVerticalLines = table.getShowVerticalLines();
 			table.setShowVerticalLines( false );
 		}
 
-		if( intercellSpacing != null ) {
+		if( intercellSpacing != null && (watcher == null || !watcher.intercellSpacingChanged) ) {
 			oldIntercellSpacing = table.getIntercellSpacing();
 			table.setIntercellSpacing( intercellSpacing );
 		}
+
+		if( watcher != null )
+			watcher.enabled = true;
+		else
+			table.addPropertyChangeListener( new FlatTablePropertyWatcher() );
+
+		// install boolean renderer
+		oldBooleanRenderer = table.getDefaultRenderer( Boolean.class );
+		if( oldBooleanRenderer instanceof UIResource )
+			table.setDefaultRenderer( Boolean.class, new FlatBooleanRenderer() );
+		else
+			oldBooleanRenderer = null;
 	}
 
 	@Override
@@ -177,15 +207,36 @@ public class FlatTableUI
 
 		oldStyleValues = null;
 
+		FlatTablePropertyWatcher watcher = FlatTablePropertyWatcher.get( table );
+		if( watcher != null )
+			watcher.enabled = false;
+
 		// restore old show horizontal/vertical lines (if not modified)
-		if( !showHorizontalLines && oldShowHorizontalLines && !table.getShowHorizontalLines() )
+		if( !showHorizontalLines && oldShowHorizontalLines && !table.getShowHorizontalLines() &&
+			(watcher == null || !watcher.showHorizontalLinesChanged) )
 		  table.setShowHorizontalLines( true );
-		if( !showVerticalLines && oldShowVerticalLines && !table.getShowVerticalLines() )
+		if( !showVerticalLines && oldShowVerticalLines && !table.getShowVerticalLines() &&
+			(watcher == null || !watcher.showVerticalLinesChanged) )
 		  table.setShowVerticalLines( true );
 
 		// restore old intercell spacing (if not modified)
-		if( intercellSpacing != null && table.getIntercellSpacing().equals( intercellSpacing ) )
+		if( intercellSpacing != null && table.getIntercellSpacing().equals( intercellSpacing ) &&
+			(watcher == null || !watcher.intercellSpacingChanged) )
 		  table.setIntercellSpacing( oldIntercellSpacing );
+
+		if( watcher != null )
+			watcher.enabled = true;
+
+		// uninstall boolean renderer
+		if( table.getDefaultRenderer( Boolean.class ) instanceof FlatBooleanRenderer ) {
+			if( oldBooleanRenderer instanceof Component ) {
+				// because the old renderer component was not attached to any component hierarchy,
+				// its UI was not yet updated, and it is necessary to do it here
+				SwingUtilities.updateComponentTreeUI( (Component) oldBooleanRenderer );
+			}
+			table.setDefaultRenderer( Boolean.class, oldBooleanRenderer );
+		}
+		oldBooleanRenderer = null;
 	}
 
 	@Override
@@ -238,6 +289,18 @@ public class FlatTableUI
 		};
 	}
 
+	@Override
+	protected void installKeyboardActions() {
+		super.installKeyboardActions();
+
+		if( UIManager.getBoolean( "Table.editorSelectAllOnStartEditing" ) ) {
+			// get shared action map, used for all tables
+			ActionMap map = SwingUtilities.getUIActionMap( table );
+			if( map != null )
+				StartEditingAction.install( map, "startEditing" );
+		}
+	}
+
 	/** @since 2 */
 	protected void installStyle() {
 		try {
@@ -467,4 +530,102 @@ public class FlatTableUI
 			}
 		}
 	}
+
+	//---- class FlatTablePropertyWatcher -------------------------------------
+
+	/**
+	 * Listener that watches for change of some table properties from application code.
+	 * This information is used in {@link FlatTableUI#installDefaults()} and
+	 * {@link FlatTableUI#uninstallDefaults()} to decide whether FlatLaf modifies those properties.
+	 * If they are modified in application code, FlatLaf no longer changes them.
+	 *
+	 * The listener is added once for each table, but never removed.
+	 * So switching Laf/theme reuses existing listener.
+	 */
+	private static class FlatTablePropertyWatcher
+		implements PropertyChangeListener
+	{
+		boolean enabled = true;
+		boolean showHorizontalLinesChanged;
+		boolean showVerticalLinesChanged;
+		boolean intercellSpacingChanged;
+
+		static FlatTablePropertyWatcher get( JTable table ) {
+			for( PropertyChangeListener l : table.getPropertyChangeListeners() ) {
+				if( l instanceof FlatTablePropertyWatcher )
+					return (FlatTablePropertyWatcher) l;
+			}
+			return null;
+		}
+
+		//---- interface PropertyChangeListener ----
+
+		@Override
+		public void propertyChange( PropertyChangeEvent e ) {
+			if( !enabled )
+				return;
+
+			switch( e.getPropertyName() ) {
+				case "showHorizontalLines":	showHorizontalLinesChanged = true; break;
+				case "showVerticalLines":	showVerticalLinesChanged = true; break;
+				case "rowMargin":			intercellSpacingChanged = true; break;
+			}
+		}
+	}
+
+	//---- class FlatBooleanRenderer ------------------------------------------
+
+	private static class FlatBooleanRenderer
+		extends DefaultTableCellRenderer
+		implements UIResource
+	{
+		private boolean selected;
+
+		FlatBooleanRenderer() {
+			setHorizontalAlignment( SwingConstants.CENTER );
+			setIcon( new FlatCheckBoxIcon() {
+				@Override
+				protected boolean isSelected( Component c ) {
+					return selected;
+				}
+			} );
+		}
+
+		@Override
+		protected void setValue( Object value ) {
+			selected = (value != null && (Boolean) value);
+		}
+	}
+
+	//---- class StartEditingAction -------------------------------------------
+
+	private static class StartEditingAction
+		extends FlatUIAction
+	{
+		static void install( ActionMap map, String key ) {
+			Action oldAction = map.get( key );
+			if( oldAction == null || oldAction instanceof StartEditingAction )
+				return; // not found or already installed
+
+			map.put( key, new StartEditingAction( oldAction ) );
+		}
+
+		private StartEditingAction( Action delegate ) {
+			super( delegate );
+		}
+
+		@Override
+		public void actionPerformed( ActionEvent e ) {
+			JTable table = (JTable) e.getSource();
+
+			Component oldEditorComp = table.getEditorComponent();
+
+			delegate.actionPerformed( e );
+
+			// select all text in editor if editing starts with F2 key
+			Component editorComp = table.getEditorComponent();
+			if( oldEditorComp == null && editorComp instanceof JTextField )
+				((JTextField)editorComp).selectAll();
+		}
+	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatTitlePane.java

@@ -36,6 +36,7 @@ import java.awt.Rectangle;
 import java.awt.Toolkit;
 import java.awt.Window;
 import java.awt.event.ActionListener;
+import java.awt.event.ComponentAdapter;
 import java.awt.event.ComponentEvent;
 import java.awt.event.ComponentListener;
 import java.awt.event.MouseEvent;
@@ -46,9 +47,9 @@ import java.awt.event.WindowEvent;
 import java.awt.geom.AffineTransform;
 import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
-import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
+import java.util.function.Function;
 import javax.accessibility.AccessibleContext;
 import javax.swing.BorderFactory;
 import javax.swing.Box;
@@ -57,7 +58,6 @@ import javax.swing.Icon;
 import javax.swing.JButton;
 import javax.swing.JComponent;
 import javax.swing.JDialog;
-import javax.swing.JInternalFrame;
 import javax.swing.JLabel;
 import javax.swing.JMenuBar;
 import javax.swing.JPanel;
@@ -66,6 +66,7 @@ import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
 import javax.swing.border.AbstractBorder;
 import javax.swing.border.Border;
+import javax.swing.plaf.ComponentUI;
 import com.formdev.flatlaf.FlatClientProperties;
 import com.formdev.flatlaf.FlatSystemProperties;
 import com.formdev.flatlaf.ui.FlatNativeWindowBorder.WindowTopBorder;
@@ -98,7 +99,6 @@ import com.formdev.flatlaf.util.UIScale;
  * @uiDefault TitlePane.showIconBesideTitle					boolean
  * @uiDefault TitlePane.menuBarTitleGap						int
  * @uiDefault TitlePane.menuBarTitleMinimumGap				int
- * @uiDefault TitlePane.menuBarResizeHeight					int
  * @uiDefault TitlePane.closeIcon							Icon
  * @uiDefault TitlePane.iconifyIcon							Icon
  * @uiDefault TitlePane.maximizeIcon						Icon
@@ -109,7 +109,8 @@ import com.formdev.flatlaf.util.UIScale;
 public class FlatTitlePane
 	extends JComponent
 {
-	private static final String KEY_DEBUG_SHOW_RECTANGLES = "FlatLaf.debug.titlebar.showRectangles";
+	static final String KEY_DEBUG_SHOW_RECTANGLES = "FlatLaf.debug.titlebar.showRectangles";
+	private static final boolean isWindows_10 = SystemInfo.isWindows_10_orLater && !SystemInfo.isWindows_11_orLater;
 
 	/** @since 2.5 */ protected final Font titleFont;
 	protected final Color activeBackground;
@@ -131,7 +132,6 @@ public class FlatTitlePane
 	/** @since 2.4 */ protected final boolean showIconBesideTitle;
 	protected final int menuBarTitleGap;
 	/** @since 2.4 */ protected final int menuBarTitleMinimumGap;
-	/** @since 2.4 */ protected final int menuBarResizeHeight;
 
 	protected final JRootPane rootPane;
 	protected final String windowStyle;
@@ -150,6 +150,33 @@ public class FlatTitlePane
 
 	private final Handler handler;
 
+	/**
+	 * This panel handles mouse events if FlatLaf window decorations are used
+	 * without native window border. E.g. on Linux.
+	 * <p>
+	 * This panel usually has same bounds as the title pane,
+	 * except if fullWindowContent mode is enabled.
+	 * <p>
+	 * This panel is not a child of the title pane.
+	 * Instead it is added by FlatRootPaneUI to the layered pane at a layer
+	 * under the title pane and under the frame content.
+	 * The separation is necessary for fullWindowContent mode, where the title pane
+	 * is layered over the frame content (for title pane buttons), but the mousePanel
+	 * needs to be layered under the frame content so that components on content pane
+	 * can receive mouse events when located in title area.
+	 */
+	final JPanel mouseLayer;
+
+	/**
+	 * This panel paint a border at the top of the window in fullWindowContent mode,
+	 * if FlatLaf window decorations are enabled.
+	 * Only used on Windows 10.
+	 * <p>
+	 * This panel is not a child of the title pane.
+	 * Instead it is added by FlatRootPaneUI to the layered pane at a layer over all other layers.
+	 */
+	final JPanel windowTopBorderLayer;
+
 	public FlatTitlePane( JRootPane rootPane ) {
 		this.rootPane = rootPane;
 
@@ -178,7 +205,6 @@ public class FlatTitlePane
 		showIconBesideTitle = FlatUIUtils.getSubUIBoolean( "TitlePane.showIconBesideTitle", windowStyle, false );
 		menuBarTitleGap = FlatUIUtils.getSubUIInt( "TitlePane.menuBarTitleGap", windowStyle, 40 );
 		menuBarTitleMinimumGap = FlatUIUtils.getSubUIInt( "TitlePane.menuBarTitleMinimumGap", windowStyle, 12 );
-		menuBarResizeHeight = FlatUIUtils.getSubUIInt( "TitlePane.menuBarResizeHeight", windowStyle, 4 );
 
 
 		handler = createHandler();
@@ -187,11 +213,18 @@ public class FlatTitlePane
 		addSubComponents();
 		activeChanged( true );
 
-		addMouseListener( handler );
-		addMouseMotionListener( handler );
+		mouseLayer = new JPanel();
+		mouseLayer.setOpaque( false );
+		mouseLayer.addMouseListener( handler );
+		mouseLayer.addMouseMotionListener( handler );
 
-		// necessary for closing window with double-click on icon
-		iconLabel.addMouseListener( handler );
+		if( isWindows_10 && FlatNativeWindowBorder.isSupported() ) {
+			windowTopBorderLayer = new JPanel();
+			windowTopBorderLayer.setVisible( false );
+			windowTopBorderLayer.setOpaque( false );
+			windowTopBorderLayer.setBorder( FlatUIUtils.nonUIResource( FlatNativeWindowBorder.WindowTopBorder.getInstance() ) );
+		} else
+			windowTopBorderLayer = null;
 
 		applyComponentOrientation( rootPane.getComponentOrientation() );
 	}
@@ -234,6 +267,11 @@ public class FlatTitlePane
 		setLayout( new BorderLayout() {
 			@Override
 			public void layoutContainer( Container target ) {
+				if( isFullWindowContent() ) {
+					super.layoutContainer( target );
+					return;
+				}
+
 				// compute available bounds
 				Insets insets = target.getInsets();
 				int x = insets.left;
@@ -247,7 +285,7 @@ public class FlatTitlePane
 				int titleWidth = w - leftWidth - buttonsWidth;
 				int minTitleWidth = UIScale.scale( titleMinimumWidth );
 
-				// increase minimum width if icon is show besides the title
+				// increase minimum width if icon is shown besides the title
 				Icon icon = titleLabel.getIcon();
 				if( icon != null ) {
 					Insets iconInsets = iconLabel.getInsets();
@@ -295,6 +333,9 @@ public class FlatTitlePane
 							horizontalGlue.getWidth(), titleLabel.getHeight() );
 					}
 				}
+
+				// clear hit-test cache
+				lastCaptionHitTestTime = 0;
 			}
 		} );
 
@@ -338,6 +379,13 @@ public class FlatTitlePane
 			buttonPanel.add( restoreButton );
 		}
 		buttonPanel.add( closeButton );
+
+		ComponentListener l = new ComponentAdapter() {
+			@Override public void componentResized( ComponentEvent e ) { updateFullWindowContentButtonsBoundsProperty(); }
+			@Override public void componentMoved( ComponentEvent e ) { updateFullWindowContentButtonsBoundsProperty(); }
+		};
+		buttonPanel.addComponentListener( l );
+		addComponentListener( l );
 	}
 
 	protected JButton createButton( String iconKey, String accessibleName, ActionListener action ) {
@@ -417,7 +465,9 @@ public class FlatTitlePane
 
 	/** @since 3 */
 	protected void updateVisibility() {
-		titleLabel.setVisible( clientPropertyBoolean( rootPane, TITLE_BAR_SHOW_TITLE, true ) );
+		boolean isFullWindowContent = isFullWindowContent();
+		leftPanel.setVisible( !isFullWindowContent );
+		titleLabel.setVisible( clientPropertyBoolean( rootPane, TITLE_BAR_SHOW_TITLE, true ) && !isFullWindowContent );
 		closeButton.setVisible( clientPropertyBoolean( rootPane, TITLE_BAR_SHOW_CLOSE, true ) );
 
 		if( window instanceof Frame ) {
@@ -443,7 +493,7 @@ public class FlatTitlePane
 
 		// get window images
 		List<Image> images = null;
-		if( clientPropertyBoolean( rootPane, TITLE_BAR_SHOW_ICON, defaultShowIcon ) ) {
+		if( clientPropertyBoolean( rootPane, TITLE_BAR_SHOW_ICON, defaultShowIcon ) && !isFullWindowContent() ) {
 			images = window.getIconImages();
 			if( images.isEmpty() ) {
 				// search in owners
@@ -468,6 +518,13 @@ public class FlatTitlePane
 		updateNativeTitleBarHeightAndHitTestSpotsLater();
 	}
 
+	void updateFullWindowContentButtonsBoundsProperty() {
+		Rectangle bounds = isFullWindowContent()
+			? new Rectangle( SwingUtilities.convertPoint( buttonPanel, 0, 0, rootPane ), buttonPanel.getSize() )
+			: null;
+		rootPane.putClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_BOUNDS, bounds );
+	}
+
 	@Override
 	public void addNotify() {
 		super.addNotify();
@@ -522,6 +579,11 @@ public class FlatTitlePane
 		window.removeComponentListener( handler );
 	}
 
+	/** @since 3.4 */
+	protected boolean isFullWindowContent() {
+		return FlatRootPaneUI.isFullWindowContent( rootPane );
+	}
+
 	/**
 	 * Returns whether this title pane currently has a visible and embedded menubar.
 	 */
@@ -533,6 +595,9 @@ public class FlatTitlePane
 	 * Returns whether the menubar should be embedded into the title pane.
 	 */
 	protected boolean isMenuBarEmbedded() {
+		if( isFullWindowContent() )
+			return false;
+
 		// not storing value of "TitlePane.menuBarEmbedded" in class to allow changing at runtime
 		return FlatUIUtils.getBoolean( rootPane,
 			FlatSystemProperties.MENUBAR_EMBEDDED,
@@ -608,6 +673,10 @@ public class FlatTitlePane
 		doLayout();
 	}
 
+	void menuBarInvalidate() {
+		menuBarPlaceholder.invalidate();
+	}
+
 	@Override
 	public void paint( Graphics g ) {
 		super.paint( g );
@@ -616,21 +685,45 @@ public class FlatTitlePane
 			return;
 
 		if( debugTitleBarHeight > 0 ) {
+			// title bar height is measured from window top edge
+			int y = SwingUtilities.convertPoint( window, 0, debugTitleBarHeight, this ).y;
 			g.setColor( Color.green );
-			g.drawLine( 0, debugTitleBarHeight, getWidth(), debugTitleBarHeight );
-		}
-		if( debugHitTestSpots != null ) {
-			for( Rectangle r : debugHitTestSpots )
-				paintRect( g, Color.red, r );
-		}
-		paintRect( g, Color.cyan, debugCloseButtonBounds );
-		paintRect( g, Color.blue, debugAppIconBounds );
-		paintRect( g, Color.blue, debugMinimizeButtonBounds );
-		paintRect( g, Color.magenta, debugMaximizeButtonBounds );
-		paintRect( g, Color.cyan, debugCloseButtonBounds );
+			g.drawLine( 0, y, getWidth(), y );
 		}
 
-	private void paintRect( Graphics g, Color color, Rectangle r ) {
+		g.setColor( Color.red );
+		debugPaintComponentWithMouseListener( g, Color.red, rootPane.getLayeredPane(), 0, 0 );
+
+		debugPaintRect( g, Color.blue, debugAppIconBounds );
+		debugPaintRect( g, Color.blue, debugMinimizeButtonBounds );
+		debugPaintRect( g, Color.magenta, debugMaximizeButtonBounds );
+		debugPaintRect( g, Color.cyan, debugCloseButtonBounds );
+	}
+
+	private void debugPaintComponentWithMouseListener( Graphics g, Color color, Component c, int x, int y ) {
+		if( !c.isDisplayable() || !c.isVisible() || c == mouseLayer ||
+			c == iconifyButton || c == maximizeButton || c == restoreButton || c == closeButton )
+		  return;
+
+		if( c.getMouseListeners().length > 0 ||
+			c.getMouseMotionListeners().length > 0 ||
+			c.getMouseWheelListeners().length > 0 )
+		{
+			g.drawRect( x, y, c.getWidth(), c.getHeight() );
+			return;
+		}
+
+		if( c instanceof Container ) {
+			Rectangle titlePaneBoundsOnWindow = SwingUtilities.convertRectangle( this, new Rectangle( getSize() ), window );
+			for( Component child : ((Container)c).getComponents() ) {
+				Rectangle compBoundsOnWindow = SwingUtilities.convertRectangle( c, new Rectangle( c.getSize() ), window );
+				if( compBoundsOnWindow.intersects( titlePaneBoundsOnWindow ) )
+					debugPaintComponentWithMouseListener( g, color, child, x + child.getX(), y + child.getY() );
+			}
+		}
+	}
+
+	private void debugPaintRect( Graphics g, Color color, Rectangle r ) {
 		if( r == null )
 			return;
 
@@ -641,6 +734,9 @@ public class FlatTitlePane
 
 	@Override
 	protected void paintComponent( Graphics g ) {
+		if( isFullWindowContent() )
+			return;
+
 		// not storing value of "TitlePane.unifiedBackground" in class to allow changing at runtime
 		g.setColor( (UIManager.getBoolean( "TitlePane.unifiedBackground" ) &&
 				clientPropertyColor( rootPane, TITLE_BAR_BACKGROUND, null ) == null)
@@ -835,10 +931,6 @@ public class FlatTitlePane
 			window.dispatchEvent( new WindowEvent( window, WindowEvent.WINDOW_CLOSING ) );
 	}
 
-	private boolean hasJBRCustomDecoration() {
-		return window != null && JBRCustomDecorations.hasCustomDecoration( window );
-	}
-
 	/**
 	 * Returns whether windows uses native window border and has custom decorations enabled.
 	 */
@@ -846,6 +938,10 @@ public class FlatTitlePane
 		return window != null && FlatNativeWindowBorder.hasCustomDecoration( window );
 	}
 
+	boolean isWindowTopBorderNeeded() {
+		return isWindows_10 && hasNativeCustomDecoration();
+	}
+
 	// used to invoke updateNativeTitleBarHeightAndHitTestSpots() only once from latest invokeLater()
 	private int laterCounter;
 
@@ -866,11 +962,14 @@ public class FlatTitlePane
 			return;
 
 		int titleBarHeight = getHeight();
+		// title bar height must be measured from window top edge
+		// (when window is maximized, window y location is e.g. -11 and window top inset is 11)
+		for( Component c = this; c != window && c != null; c = c.getParent() )
+			titleBarHeight += c.getY();
 		// slightly reduce height so that component receives mouseExit events
 		if( titleBarHeight > 0 )
 			titleBarHeight--;
 
-		List<Rectangle> hitTestSpots = new ArrayList<>();
 		Rectangle appIconBounds = null;
 
 		if( !showIconBesideTitle && iconLabel.isVisible() ) {
@@ -896,9 +995,6 @@ public class FlatTitlePane
 					iconBounds.width += iconInsets.right;
 			}
 
-			if( hasJBRCustomDecoration() )
-				hitTestSpots.add( iconBounds );
-			else
 			appIconBounds = iconBounds;
 		} else if( showIconBesideTitle && titleLabel.getIcon() != null && titleLabel.getUI() instanceof FlatTitleLabelUI ) {
 			FlatTitleLabelUI ui = (FlatTitleLabelUI) titleLabel.getUI();
@@ -927,78 +1023,21 @@ public class FlatTitlePane
 				iconR.width += 2;
 				iconR.height += 2;
 
-				if( hasJBRCustomDecoration() )
-					hitTestSpots.add( iconR );
-				else
 				appIconBounds = iconR;
 			}
 		}
 
-		Rectangle r = getNativeHitTestSpot( buttonPanel );
-		if( r != null )
-			hitTestSpots.add( r );
-
-		JMenuBar menuBar = rootPane.getJMenuBar();
-		if( hasVisibleEmbeddedMenuBar( menuBar ) ) {
-			r = getNativeHitTestSpot( menuBar );
-			if( r != null ) {
-				// if frame is resizable and not maximized, make menu bar hit test spot smaller at top
-				// to have a small area above the menu bar to resize the window
-				if( window instanceof Frame && ((Frame)window).isResizable() && !isWindowMaximized() ) {
-					// limit to 8, because Windows does not use a larger height
-					int resizeHeight = UIScale.scale( Math.min( menuBarResizeHeight, 8 ) );
-					r.y += resizeHeight;
-					r.height -= resizeHeight;
-				}
-
-				int count = menuBar.getComponentCount();
-				for( int i = count - 1; i >= 0; i-- ) {
-					Component c = menuBar.getComponent( i );
-					if( c instanceof Box.Filler ||
-						(c instanceof JComponent && clientPropertyBoolean( (JComponent) c, COMPONENT_TITLE_BAR_CAPTION, false ) ) )
-					{
-						// If menu bar is embedded and contains a horizontal glue or caption component,
-						// then split the hit test spot so that
-						// the glue/caption component area can be used to move the window.
-
-						Point glueLocation = SwingUtilities.convertPoint( c, 0, 0, window );
-						int x2 = glueLocation.x + c.getWidth();
-						Rectangle r2;
-						if( getComponentOrientation().isLeftToRight() ) {
-							r2 = new Rectangle( x2, r.y, (r.x + r.width) - x2, r.height );
-
-							r.width = glueLocation.x - r.x;
-						} else {
-							r2 = new Rectangle( r.x, r.y, glueLocation.x - r.x, r.height );
-
-							r.width = (r.x + r.width) - x2;
-							r.x = x2;
-						}
-						if( r2.width > 0 )
-							hitTestSpots.add( r2 );
-					}
-				}
-
-				hitTestSpots.add( r );
-			}
-		}
-
-		// allow internal frames in layered pane to be moved/resized when placed over title bar
-		for( Component c : rootPane.getLayeredPane().getComponents() ) {
-			r = (c instanceof JInternalFrame) ? getNativeHitTestSpot( (JInternalFrame) c ) : null;
-			if( r != null )
-				hitTestSpots.add( r );
-		}
-
 		Rectangle minimizeButtonBounds = boundsInWindow( iconifyButton );
 		Rectangle maximizeButtonBounds = boundsInWindow( maximizeButton.isVisible() ? maximizeButton : restoreButton );
 		Rectangle closeButtonBounds = boundsInWindow( closeButton );
 
+		// clear hit-test cache
+		lastCaptionHitTestTime = 0;
+
 		FlatNativeWindowBorder.setTitleBarHeightAndHitTestSpots( window, titleBarHeight,
-			hitTestSpots, appIconBounds, minimizeButtonBounds, maximizeButtonBounds, closeButtonBounds );
+			this::captionHitTest, appIconBounds, minimizeButtonBounds, maximizeButtonBounds, closeButtonBounds );
 
 		debugTitleBarHeight = titleBarHeight;
-		debugHitTestSpots = hitTestSpots;
 		debugAppIconBounds = appIconBounds;
 		debugMinimizeButtonBounds = minimizeButtonBounds;
 		debugMaximizeButtonBounds = maximizeButtonBounds;
@@ -1013,18 +1052,101 @@ public class FlatTitlePane
 			: null;
 	}
 
-	protected Rectangle getNativeHitTestSpot( JComponent c ) {
-		Dimension size = c.getSize();
-		if( size.width <= 0 || size.height <= 0 )
-			return null;
-
-		Point location = SwingUtilities.convertPoint( c, 0, 0, window );
-		Rectangle r = new Rectangle( location, size );
-		return r;
+	/**
+	 * Returns whether there is a component at the given location, that processes
+	 * mouse events. E.g. buttons, menus, etc.
+	 * <p>
+	 * Note:
+	 * <ul>
+	 *   <li>This method is invoked often when mouse is moved over title bar
+	 *       and should therefore return quickly.
+	 *   <li>This method is invoked on 'AWT-Windows' thread (not 'AWT-EventQueue' thread)
+	 *       while processing Windows messages.
+	 * </ul>
+	 */
+	private boolean captionHitTest( Point pt ) {
+		// Windows invokes this method every ~200ms, even if the mouse has not moved
+		long time = System.currentTimeMillis();
+		if( pt.x == lastCaptionHitTestX && pt.y == lastCaptionHitTestY && time < lastCaptionHitTestTime + 300 ) {
+			lastCaptionHitTestTime = time;
+			return lastCaptionHitTestResult;
 		}
 
+		// convert pt from window coordinates to layeredPane coordinates
+		Component layeredPane = rootPane.getLayeredPane();
+		int x = pt.x;
+		int y = pt.y;
+		for( Component c = layeredPane; c != window && c != null; c = c.getParent() ) {
+			x -= c.getX();
+			y -= c.getY();
+		}
+
+		lastCaptionHitTestX = pt.x;
+		lastCaptionHitTestY = pt.y;
+		lastCaptionHitTestTime = time;
+		lastCaptionHitTestResult = isTitleBarCaptionAt( layeredPane, x, y );
+		return lastCaptionHitTestResult;
+	}
+
+	private boolean isTitleBarCaptionAt( Component c, int x, int y ) {
+		if( !c.isDisplayable() || !c.isVisible() || !c.contains( x, y ) || c == mouseLayer )
+			return true; // continue checking with next component
+
+		if( c.isEnabled() &&
+			(c.getMouseListeners().length > 0 ||
+			 c.getMouseMotionListeners().length > 0) )
+		{
+			if( !(c instanceof JComponent) )
+				return false; // assume that this is not a caption because the component has mouse listeners
+
+			// check client property boolean value
+			Object caption = ((JComponent)c).getClientProperty( COMPONENT_TITLE_BAR_CAPTION );
+			if( caption instanceof Boolean )
+				return (boolean) caption;
+
+			// if component is not fully layouted, do not invoke function
+			// because it is too dangerous that the function tries to layout the component,
+			// which could cause a dead lock
+			if( !c.isValid() )
+				return false; // assume that this is not a caption because the component has mouse listeners
+
+			if( caption instanceof Function ) {
+				// check client property function value
+				@SuppressWarnings( "unchecked" )
+				Function<Point, Boolean> hitTest = (Function<Point, Boolean>) caption;
+				Boolean result = hitTest.apply( new Point( x, y ) );
+				if( result != null )
+					return result;
+			} else {
+				// check component UI
+				ComponentUI ui = JavaCompatibility2.getUI( (JComponent) c );
+				if( !(ui instanceof TitleBarCaptionHitTest) )
+					return false; // assume that this is not a caption because the component has mouse listeners
+
+				Boolean result = ((TitleBarCaptionHitTest)ui).isTitleBarCaptionAt( x, y );
+				if( result != null )
+					return result;
+			}
+
+			// else continue checking children
+		}
+
+		// check children
+		if( c instanceof Container ) {
+			for( Component child : ((Container)c).getComponents() ) {
+				if( !isTitleBarCaptionAt( child, x - child.getX(), y - child.getY() ) )
+					return false;
+			}
+		}
+		return true;
+	}
+
+	private int lastCaptionHitTestX;
+	private int lastCaptionHitTestY;
+	private long lastCaptionHitTestTime;
+	private boolean lastCaptionHitTestResult;
+
 	private int debugTitleBarHeight;
-	private List<Rectangle> debugHitTestSpots;
 	private Rectangle debugAppIconBounds;
 	private Rectangle debugMinimizeButtonBounds;
 	private Rectangle debugMaximizeButtonBounds;
@@ -1047,7 +1169,7 @@ public class FlatTitlePane
 			} else if( borderColor != null && (rootPane.getJMenuBar() == null || !rootPane.getJMenuBar().isVisible()) )
 				insets.bottom += UIScale.scale( 1 );
 
-			if( !SystemInfo.isWindows_11_orLater && hasNativeCustomDecoration() && !isWindowMaximized() )
+			if( isWindowTopBorderNeeded() && !isWindowMaximized() )
 				insets = FlatUIUtils.addInsets( insets, WindowTopBorder.getInstance().getBorderInsets() );
 
 			return insets;
@@ -1066,7 +1188,7 @@ public class FlatTitlePane
 				FlatUIUtils.paintFilledRectangle( g, borderColor, x, y + height - lineHeight, width, lineHeight );
 			}
 
-			if( !SystemInfo.isWindows_11_orLater && hasNativeCustomDecoration() && !isWindowMaximized() )
+			if( isWindowTopBorderNeeded() && !isWindowMaximized() && !isFullWindowContent() )
 				WindowTopBorder.getInstance().paintBorder( c, g, x, y, width, height );
 		}
 
@@ -1122,7 +1244,7 @@ public class FlatTitlePane
 				}
 			}
 
-			// compute icon width and gap (if icon is show besides the title)
+			// compute icon width and gap (if icon is shown besides the title)
 			int iconTextGap = 0;
 			int iconWidthAndGap = 0;
 			if( icon != null ) {
@@ -1131,7 +1253,7 @@ public class FlatTitlePane
 				iconWidthAndGap = icon.getIconWidth() + iconTextGap;
 			}
 
-			// layout title and icon (if show besides the title)
+			// layout title and icon (if shown besides the title)
 			String clippedText = SwingUtilities.layoutCompoundLabel( label, fontMetrics, text, icon,
 				label.getVerticalAlignment(), label.getHorizontalAlignment(),
 				label.getVerticalTextPosition(), label.getHorizontalTextPosition(),
@@ -1230,7 +1352,7 @@ public class FlatTitlePane
 			activeChanged( true );
 			updateNativeTitleBarHeightAndHitTestSpots();
 
-			if( !SystemInfo.isWindows_11_orLater && hasNativeCustomDecoration() )
+			if( isWindowTopBorderNeeded() )
 				WindowTopBorder.getInstance().repaintBorder( FlatTitlePane.this );
 
 			repaintWindowBorder();
@@ -1241,7 +1363,7 @@ public class FlatTitlePane
 			activeChanged( false );
 			updateNativeTitleBarHeightAndHitTestSpots();
 
-			if( !SystemInfo.isWindows_11_orLater && hasNativeCustomDecoration() )
+			if( isWindowTopBorderNeeded() )
 				WindowTopBorder.getInstance().repaintBorder( FlatTitlePane.this );
 
 			repaintWindowBorder();
@@ -1270,7 +1392,7 @@ debug*/
 		public void mouseClicked( MouseEvent e ) {
 			// on Linux, when using native library, the mouse clicked event
 			// is usually not sent and maximize/restore is done in mouse pressed event
-			// this check is here for the case that a mouse clicked event comes thru for some reason
+			// this check is here for the case that a mouse clicked event comes through for some reason
 			if( linuxNativeMove && SystemInfo.isLinux && FlatNativeLinuxLibrary.isWMUtilsSupported( window ) ) {
 				// see comment in mousePressed()
 				if( lastSingleClickWhen != 0 && (e.getWhen() - lastSingleClickWhen) <= getMultiClickInterval() ) {
@@ -1281,7 +1403,7 @@ debug*/
 			}
 
 			if( e.getClickCount() == 2 && SwingUtilities.isLeftMouseButton( e ) ) {
-				if( e.getSource() == iconLabel ) {
+				if( SwingUtilities.getDeepestComponentAt( FlatTitlePane.this, e.getX(), e.getY() ) == iconLabel ) {
 					// double-click on icon closes window
 					close();
 				} else if( !hasNativeCustomDecoration() ) {
@@ -1308,7 +1430,7 @@ debug*/
 			if( !SwingUtilities.isLeftMouseButton( e ) )
 				return;
 
-			dragOffset = SwingUtilities.convertPoint( FlatTitlePane.this, e.getPoint(), window );
+			dragOffset = SwingUtilities.convertPoint( mouseLayer, e.getPoint(), window );
 			linuxNativeMove = false;
 
 			// on Linux, move or maximize/restore window
@@ -1421,4 +1543,27 @@ debug*/
 		@Override public void componentMoved( ComponentEvent e ) {}
 		@Override public void componentHidden( ComponentEvent e ) {}
 	}
+
+	//---- interface TitleBarCaptionHitTest -----------------------------------
+
+	/**
+	 * For custom components use {@link FlatClientProperties#COMPONENT_TITLE_BAR_CAPTION}
+	 * instead of this interface.
+	 *
+	 * @since 3.4
+	 */
+	public interface TitleBarCaptionHitTest {
+		/**
+		 * Invoked for a component that is enabled and has mouse listeners,
+		 * to check whether it processes mouse input at the given x/y location.
+		 * Useful for components that do not use mouse input on whole component bounds.
+		 * E.g. a tabbed pane with a few tabs has some empty space beside the tabs
+		 * that can be used to move the window.
+		 *
+		 * @return {@code true} if the component is not interested in mouse input at the given location
+		 *         {@code false} if the component wants process mouse input at the given location
+		 *         {@code null} if the component children should be checked
+		 */
+		Boolean isTitleBarCaptionAt( int x, int y );
+	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatToolBarSeparatorUI.java

@@ -18,6 +18,7 @@ package com.formdev.flatlaf.ui;
 
 import static com.formdev.flatlaf.util.UIScale.scale;
 import java.awt.Color;
+import java.awt.Container;
 import java.awt.Dimension;
 import java.awt.Graphics;
 import java.awt.Graphics2D;
@@ -173,6 +174,12 @@ public class FlatToolBarSeparatorUI
 		if( size != null )
 			return scale( size );
 
+		// get separator width
+		int separatorWidth = this.separatorWidth;
+		FlatToolBarUI toolBarUI = getToolBarUI( c );
+		if( toolBarUI != null && toolBarUI.separatorWidth != null )
+			separatorWidth = toolBarUI.separatorWidth;
+
 		// make sure that gap on left and right side of line have same size
 		int sepWidth = (scale( (separatorWidth - LINE_WIDTH) / 2 ) * 2) + scale( LINE_WIDTH );
 
@@ -196,6 +203,12 @@ public class FlatToolBarSeparatorUI
 		float lineWidth = scale( 1f );
 		float offset = scale( 2f );
 
+		// get separator color
+		Color separatorColor = this.separatorColor;
+		FlatToolBarUI toolBarUI = getToolBarUI( c );
+		if( toolBarUI != null && toolBarUI.separatorColor != null )
+			separatorColor = toolBarUI.separatorColor;
+
 		Object[] oldRenderingHints = FlatUIUtils.setRenderingHints( g );
 		g.setColor( separatorColor );
 
@@ -210,4 +223,11 @@ public class FlatToolBarSeparatorUI
 	private boolean isVertical( JComponent c ) {
 		return ((JToolBar.Separator)c).getOrientation() == SwingConstants.VERTICAL;
 	}
+
+	private FlatToolBarUI getToolBarUI( JComponent c ) {
+		Container parent = c.getParent();
+		return (parent instanceof JToolBar && ((JToolBar)parent).getUI() instanceof FlatToolBarUI)
+			? (FlatToolBarUI) ((JToolBar)parent).getUI()
+			: null;
+	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatToolBarUI.java

@@ -82,7 +82,7 @@ import com.formdev.flatlaf.util.UIScale;
  */
 public class FlatToolBarUI
 	extends BasicToolBarUI
-	implements StyleableUI
+	implements StyleableUI, FlatTitlePane.TitleBarCaptionHitTest
 {
 	/** @since 1.4 */ @Styleable protected boolean focusableButtons;
 	/** @since 2 */ @Styleable protected boolean arrowKeysOnlyNavigation;
@@ -93,6 +93,10 @@ public class FlatToolBarUI
 	@Styleable protected Insets borderMargins;
 	@Styleable protected Color gripColor;
 
+	// for FlatToolBarSeparatorUI
+	/** @since 3.3 */ @Styleable protected Integer separatorWidth;
+	/** @since 3.3 */ @Styleable protected Color separatorColor;
+
 	private FocusTraversalPolicy focusTraversalPolicy;
 	private Boolean oldFloatable;
 	private Map<String, Object> oldStyleValues;
@@ -449,6 +453,15 @@ public class FlatToolBarUI
 			: null;
 	}
 
+	//---- interface FlatTitlePane.TitleBarCaptionHitTest ----
+
+	/** @since 3.4 */
+	@Override
+	public Boolean isTitleBarCaptionAt( int x, int y ) {
+		// necessary because BasicToolBarUI adds some mouse listeners for dragging when toolbar is floatable
+		return null; // check children
+	}
+
 	//---- class FlatToolBarFocusTraversalPolicy ------------------------------
 
 	/**

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatUIAction.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2024 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.formdev.flatlaf.ui;
+
+import java.beans.PropertyChangeListener;
+import javax.swing.Action;
+
+/**
+ * Base class for UI actions used in ActionMap.
+ * (similar to class sun.swing.UIAction)
+ *
+ * @author Karl Tauber
+ * @since 3.4
+ */
+public abstract class FlatUIAction
+	implements Action
+{
+	protected final String name;
+	protected final Action delegate;
+
+	protected FlatUIAction( String name ) {
+		this.name = name;
+		this.delegate = null;
+	}
+
+	protected FlatUIAction( Action delegate ) {
+		this.name = null;
+		this.delegate = delegate;
+	}
+
+	@Override
+	public Object getValue( String key ) {
+		if( key == NAME && delegate == null )
+			return name;
+		return (delegate != null) ? delegate.getValue( key ) : null;
+	}
+
+	@Override
+	public boolean isEnabled() {
+		return (delegate != null) ? delegate.isEnabled() : true;
+	}
+
+	// do nothing in following methods because this class is immutable
+	@Override public void putValue( String key, Object value ) {}
+	@Override public void setEnabled( boolean b ) {}
+	@Override public void addPropertyChangeListener( PropertyChangeListener listener ) {}
+	@Override public void removePropertyChangeListener( PropertyChangeListener listener ) {}
+}

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatUIUtils.java

@@ -60,6 +60,7 @@ import javax.swing.border.Border;
 import javax.swing.border.CompoundBorder;
 import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.UIResource;
+import javax.swing.tree.DefaultTreeCellEditor;
 import com.formdev.flatlaf.FlatClientProperties;
 import com.formdev.flatlaf.FlatIntelliJLaf;
 import com.formdev.flatlaf.FlatLaf;
@@ -299,15 +300,14 @@ public class FlatUIUtils
 		if( c == null )
 			return false;
 
-		// check whether used in cell editor (check 3 levels up)
-		Component c2 = c;
-		for( int i = 0; i <= 2 && c2 != null; i++ ) {
-			Container parent = c2.getParent();
-			if( parent instanceof JTable && ((JTable)parent).getEditorComponent() == c2 )
+		// check whether used as table cell editor
+		Container parent = c.getParent();
+		if( parent instanceof JTable && ((JTable)parent).getEditorComponent() == c )
 			return true;
 
-			c2 = parent;
-		}
+		// check whether used as tree cell editor
+		if( parent instanceof DefaultTreeCellEditor.EditorContainer )
+			return true;
 
 		// check whether used as cell editor
 		//   Table.editor is set in JTable.GenericEditor constructor
@@ -734,7 +734,7 @@ public class FlatUIUtils
 	}
 
 	/**
-	 * Creates a (rounded) rectangle used to paint components (border, background, etc).
+	 * Creates a (rounded) rectangle used to paint components (border, background, etc.).
 	 * The given arc diameter is limited to min(width,height).
 	 */
 	public static Shape createComponentRectangle( float x, float y, float w, float h, float arc ) {

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatViewportUI.java

@@ -18,7 +18,6 @@ package com.formdev.flatlaf.ui;
 
 import java.awt.Component;
 import java.awt.Graphics;
-import java.lang.reflect.Method;
 import javax.swing.JComponent;
 import javax.swing.JViewport;
 import javax.swing.plaf.ComponentUI;
@@ -48,14 +47,9 @@ public class FlatViewportUI
 
 		Component view = ((JViewport)c).getView();
 		if( view instanceof JComponent ) {
-			try {
-				Method m = view.getClass().getMethod( "getUI" );
-				Object ui = m.invoke( view );
+			ComponentUI ui = JavaCompatibility2.getUI( (JComponent) view );
 			if( ui instanceof ViewportPainter )
 				((ViewportPainter)ui).paintViewport( g, (JComponent) view, (JViewport) c );
-			} catch( Exception ex ) {
-				// ignore
-			}
 		}
 	}
 

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatWindowsNativeWindowBorder.java

@@ -29,8 +29,8 @@ import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
 import java.util.Collections;
 import java.util.IdentityHashMap;
-import java.util.List;
 import java.util.Map;
+import java.util.function.Predicate;
 import javax.swing.JDialog;
 import javax.swing.JFrame;
 import javax.swing.Timer;
@@ -89,7 +89,7 @@ class FlatWindowsNativeWindowBorder
 			return null;
 
 		// check whether native library was successfully loaded
-		if( !FlatNativeLibrary.isLoaded() )
+		if( !FlatNativeWindowsLibrary.isLoaded() )
 			return null;
 
 		// create new instance
@@ -159,7 +159,7 @@ class FlatWindowsNativeWindowBorder
 	}
 
 	@Override
-	public void updateTitleBarInfo( Window window, int titleBarHeight, List<Rectangle> hitTestSpots,
+	public void updateTitleBarInfo( Window window, int titleBarHeight, Predicate<Point> captionHitTestCallback,
 		Rectangle appIconBounds, Rectangle minimizeButtonBounds, Rectangle maximizeButtonBounds,
 		Rectangle closeButtonBounds )
 	{
@@ -168,7 +168,7 @@ class FlatWindowsNativeWindowBorder
 			return;
 
 		wndProc.titleBarHeight = titleBarHeight;
-		wndProc.hitTestSpots = hitTestSpots.toArray( new Rectangle[hitTestSpots.size()] );
+		wndProc.captionHitTestCallback = captionHitTestCallback;
 		wndProc.appIconBounds = cloneRectange( appIconBounds );
 		wndProc.minimizeButtonBounds = cloneRectange( minimizeButtonBounds );
 		wndProc.maximizeButtonBounds = cloneRectange( maximizeButtonBounds );
@@ -288,8 +288,8 @@ class FlatWindowsNativeWindowBorder
 		private final long hwnd;
 
 		// Swing coordinates/values may be scaled on a HiDPI screen
-		private int titleBarHeight;
-		private Rectangle[] hitTestSpots;
+		private int titleBarHeight; // measured from window top edge, which may be out-of-screen if maximized
+		private Predicate<Point> captionHitTestCallback;
 		private Rectangle appIconBounds;
 		private Rectangle minimizeButtonBounds;
 		private Rectangle maximizeButtonBounds;
@@ -340,50 +340,61 @@ class FlatWindowsNativeWindowBorder
 		private int onNcHitTest( int x, int y, boolean isOnResizeBorder ) {
 			// scale-down mouse x/y because Swing coordinates/values may be scaled on a HiDPI screen
 			Point pt = scaleDown( x, y );
-			int sx = pt.x;
-			int sy = pt.y;
 
 			// return HTSYSMENU if mouse is over application icon
 			//   - left-click on HTSYSMENU area shows system menu
 			//   - double-left-click sends WM_CLOSE
-			if( contains( appIconBounds, sx, sy ) )
+			if( contains( appIconBounds, pt ) )
 				return HTSYSMENU;
 
 			// return HTMINBUTTON if mouse is over minimize button
 			//   - hovering mouse over HTMINBUTTON area shows tooltip on Windows 10/11
-			if( contains( minimizeButtonBounds, sx, sy ) )
+			if( contains( minimizeButtonBounds, pt ) )
 				return HTMINBUTTON;
 
 			// return HTMAXBUTTON if mouse is over maximize/restore button
 			//   - hovering mouse over HTMAXBUTTON area shows tooltip on Windows 10
 			//   - hovering mouse over HTMAXBUTTON area shows snap layouts menu on Windows 11
 			//     https://docs.microsoft.com/en-us/windows/apps/desktop/modernize/apply-snap-layout-menu
-			if( contains( maximizeButtonBounds, sx, sy ) )
+			if( contains( maximizeButtonBounds, pt ) )
 				return HTMAXBUTTON;
 
 			// return HTCLOSE if mouse is over close button
 			//   - hovering mouse over HTCLOSE area shows tooltip on Windows 10/11
-			if( contains( closeButtonBounds, sx, sy ) )
+			if( contains( closeButtonBounds, pt ) )
 				return HTCLOSE;
 
-			boolean isOnTitleBar = (sy < titleBarHeight);
+			// return HTTOP if mouse is over top resize border
+			//   - hovering mouse shows vertical resize cursor
+			//   - left-click and drag vertically resizes window
+			if( isOnResizeBorder )
+				return HTTOP;
 
+			boolean isOnTitleBar = (pt.y < titleBarHeight);
 			if( isOnTitleBar ) {
-				// use a second reference to the array to avoid that it can be changed
-				// in another thread while processing the array
-				Rectangle[] hitTestSpots2 = hitTestSpots;
-				for( Rectangle spot : hitTestSpots2 ) {
-					if( spot.contains( sx, sy ) )
+				// return HTCLIENT if mouse is over any Swing component in title bar
+				// that processes mouse events (e.g. buttons, menus, etc)
+				//   - Windows ignores mouse events in this area
+				try {
+					if( captionHitTestCallback != null && !captionHitTestCallback.test( pt ) )
+						return HTCLIENT;
+				} catch( Throwable ex ) {
+					// ignore
+				}
+
+				// return HTCAPTION if mouse is over title bar
+				//   - right-click shows system menu
+				//   - double-left-click maximizes/restores window size
+				return HTCAPTION;
+			}
+
+			// return HTCLIENT
+			//   - Windows ignores mouse events in this area
 			return HTCLIENT;
 		}
-				return isOnResizeBorder ? HTTOP : HTCAPTION;
-			}
 
-			return isOnResizeBorder ? HTTOP : HTCLIENT;
-		}
-
-		private boolean contains( Rectangle rect, int x, int y ) {
-			return (rect != null && rect.contains( x, y ) );
+		private boolean contains( Rectangle rect, Point pt ) {
+			return (rect != null && rect.contains( pt ) );
 		}
 
 		/**

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FullWindowContentSupport.java

@@ -0,0 +1,219 @@
+/*
+ * Copyright 2024 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.formdev.flatlaf.ui;
+
+import java.awt.Color;
+import java.awt.Component;
+import java.awt.Dimension;
+import java.awt.Graphics;
+import java.awt.Rectangle;
+import java.awt.Window;
+import java.awt.event.ComponentAdapter;
+import java.awt.event.ComponentEvent;
+import java.awt.event.ComponentListener;
+import java.lang.ref.WeakReference;
+import java.util.ArrayList;
+import java.util.Iterator;
+import javax.swing.JComponent;
+import javax.swing.JRootPane;
+import javax.swing.SwingUtilities;
+import javax.swing.UIManager;
+import com.formdev.flatlaf.FlatClientProperties;
+import com.formdev.flatlaf.util.SystemInfo;
+
+/**
+ * @author Karl Tauber
+ */
+class FullWindowContentSupport
+{
+	private static final String KEY_DEBUG_SHOW_PLACEHOLDERS = "FlatLaf.debug.panel.showPlaceholders";
+
+	private static ArrayList<WeakReference<JComponent>> placeholders = new ArrayList<>();
+
+	static Dimension getPlaceholderPreferredSize( JComponent c, String options ) {
+		JRootPane rootPane;
+		Rectangle bounds;
+
+		if( !options.startsWith( SystemInfo.isMacOS ? "mac" : "win" ) ||
+			!c.isDisplayable() ||
+			(rootPane = SwingUtilities.getRootPane( c )) == null ||
+			(bounds = (Rectangle) rootPane.getClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_BOUNDS )) == null )
+		  return new Dimension( 0, 0 );
+
+		if( options.length() > 3 ) {
+			if( (options.contains( "leftToRight" ) && !c.getComponentOrientation().isLeftToRight()) ||
+				(options.contains( "rightToLeft" ) && c.getComponentOrientation().isLeftToRight()) )
+			  return new Dimension( 0, 0 );
+		}
+
+		// On macOS, the client property is updated very late when toggling full screen,
+		// which results in "jumping" layout after full screen toggle finished.
+		// To avoid that, get up-to-date buttons bounds from macOS.
+		if( SystemInfo.isMacFullWindowContentSupported && FlatNativeMacLibrary.isLoaded() ) {
+			Rectangle r = FlatNativeMacLibrary.getWindowButtonsBounds( SwingUtilities.windowForComponent( c ) );
+			if( r != null )
+				bounds = r;
+		}
+
+		int width = bounds.width;
+		int height = bounds.height;
+
+		if( options.length() > 3 ) {
+			if( width == 0 && options.contains( "zeroInFullScreen" ) )
+				height = 0;
+
+			if( options.contains( "horizontal" ) )
+				height = 0;
+			if( options.contains( "vertical" ) )
+				width = 0;
+		}
+
+		return new Dimension( width, height );
+	}
+
+	static void registerPlaceholder( JComponent c ) {
+		synchronized( placeholders ) {
+			if( indexOfPlaceholder( c ) < 0 )
+				placeholders.add( new WeakReference<>( c ) );
+		}
+	}
+
+	static void unregisterPlaceholder( JComponent c ) {
+		synchronized( placeholders ) {
+			int index = indexOfPlaceholder( c );
+			if( index >= 0 )
+				placeholders.remove( index );
+		}
+	}
+
+	private static int indexOfPlaceholder( JComponent c ) {
+		int size = placeholders.size();
+		for( int i = 0; i < size; i++ ) {
+			if( placeholders.get( i ).get() == c )
+				return i;
+		}
+		return -1;
+	}
+
+	static void revalidatePlaceholders( Component container ) {
+		synchronized( placeholders ) {
+			if( placeholders.isEmpty() )
+				return;
+
+			for( Iterator<WeakReference<JComponent>> it = placeholders.iterator(); it.hasNext(); ) {
+				WeakReference<JComponent> ref = it.next();
+				JComponent c = ref.get();
+
+				// remove already released placeholder
+				if( c == null ) {
+					it.remove();
+					continue;
+				}
+
+				// revalidate placeholder if is in given container
+				if( SwingUtilities.isDescendingFrom( c, container ) )
+					c.revalidate();
+			}
+		}
+	}
+
+	static ComponentListener macInstallListeners( JRootPane rootPane ) {
+		ComponentListener l = new ComponentAdapter() {
+			boolean lastFullScreen;
+
+			@Override
+			public void componentResized( ComponentEvent e ) {
+				Window window = SwingUtilities.windowForComponent( rootPane );
+				if( window == null )
+					return;
+
+				boolean fullScreen = FlatNativeMacLibrary.isLoaded() && FlatNativeMacLibrary.isWindowFullScreen( window );
+				if( fullScreen == lastFullScreen )
+					return;
+
+				lastFullScreen = fullScreen;
+				macUpdateFullWindowContentButtonsBoundsProperty( rootPane );
+			}
+		};
+
+		rootPane.addComponentListener( l );
+		return l;
+	}
+
+	static void macUninstallListeners( JRootPane rootPane, ComponentListener l ) {
+		if( l != null )
+			rootPane.removeComponentListener( l );
+	}
+
+	static void macUpdateFullWindowContentButtonsBoundsProperty( JRootPane rootPane ) {
+		if( !SystemInfo.isMacFullWindowContentSupported || !rootPane.isDisplayable() )
+			return;
+
+		Rectangle bounds = null;
+		if( FlatClientProperties.clientPropertyBoolean( rootPane, "apple.awt.fullWindowContent", false ) ) {
+			bounds = FlatNativeMacLibrary.isLoaded()
+				? FlatNativeMacLibrary.getWindowButtonsBounds( SwingUtilities.windowForComponent( rootPane ) )
+				: new Rectangle( 68, 28 ); // default size
+		}
+		rootPane.putClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_BOUNDS, bounds );
+	}
+
+	static void macUninstallFullWindowContentButtonsBoundsProperty( JRootPane rootPane ) {
+		if( !SystemInfo.isMacFullWindowContentSupported )
+			return;
+
+		rootPane.putClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_BOUNDS, null );
+	}
+
+	static void debugPaint( Graphics g, JComponent c ) {
+		if( !UIManager.getBoolean( KEY_DEBUG_SHOW_PLACEHOLDERS ) )
+			return;
+
+		int width = c.getWidth();
+		int height = c.getHeight();
+		if( width <= 0 || height <= 0 )
+			return;
+
+		// draw red figure
+		g.setColor( Color.red );
+		debugPaintRect( g, new Rectangle( width, height ) );
+
+		// draw magenta figure if buttons bounds are not equal to placeholder bounds
+		JRootPane rootPane;
+		Rectangle bounds;
+		if( (rootPane = SwingUtilities.getRootPane( c )) != null &&
+			(bounds = (Rectangle) rootPane.getClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_BOUNDS )) != null &&
+			(bounds.width != width || bounds.height != height) )
+		{
+			g.setColor( Color.magenta );
+			debugPaintRect( g, SwingUtilities.convertRectangle( rootPane, bounds, c ) );
+		}
+	}
+
+	private static void debugPaintRect( Graphics g, Rectangle r ) {
+		// draw rectangle
+		g.drawRect( r.x, r.y, r.width - 1, r.height - 1 );
+
+		// draw diagonal cross
+		int x2 = r.x + r.width - 1;
+		int y2 = r.y + r.height - 1;
+		Object[] oldRenderingHints = FlatUIUtils.setRenderingHints( g );
+		g.drawLine( r.x, r.y, x2, y2 );
+		g.drawLine( r.x, y2, x2, r.y );
+		FlatUIUtils.resetRenderingHints( g, oldRenderingHints );
+	}
+}

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/JBRCustomDecorations.java

@@ -1,306 +0,0 @@
-/*
- * Copyright 2020 FormDev Software GmbH
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.formdev.flatlaf.ui;
-
-import java.awt.Color;
-import java.awt.Component;
-import java.awt.Container;
-import java.awt.EventQueue;
-import java.awt.Graphics;
-import java.awt.Graphics2D;
-import java.awt.Rectangle;
-import java.awt.Toolkit;
-import java.awt.Window;
-import java.awt.event.HierarchyEvent;
-import java.awt.event.HierarchyListener;
-import java.beans.PropertyChangeListener;
-import java.lang.reflect.Method;
-import java.util.Collections;
-import java.util.List;
-import javax.swing.JRootPane;
-import javax.swing.SwingUtilities;
-import javax.swing.UIManager;
-import javax.swing.plaf.BorderUIResource;
-import com.formdev.flatlaf.FlatLaf;
-import com.formdev.flatlaf.util.LoggingFacade;
-import com.formdev.flatlaf.util.HiDPIUtils;
-import com.formdev.flatlaf.util.SystemInfo;
-
-/**
- * Support for custom window decorations provided by JetBrains Runtime (based on OpenJDK).
- * Requires that the application runs on Windows 10 in a JetBrains Runtime 11 or later.
- * <ul>
- *   <li><a href="https://confluence.jetbrains.com/display/JBR/JetBrains+Runtime">https://confluence.jetbrains.com/display/JBR/JetBrains+Runtime</a></li>
- *   <li><a href="https://github.com/JetBrains/JetBrainsRuntime">https://github.com/JetBrains/JetBrainsRuntime</a></li>
- * </ul>
- *
- * @author Karl Tauber
- */
-public class JBRCustomDecorations
-{
-	private static Boolean supported;
-	private static Method Window_hasCustomDecoration;
-	private static Method Window_setHasCustomDecoration;
-	private static Method WWindowPeer_setCustomDecorationTitleBarHeight;
-	private static Method WWindowPeer_setCustomDecorationHitTestSpots;
-	private static Method AWTAccessor_getComponentAccessor;
-	private static Method AWTAccessor_ComponentAccessor_getPeer;
-
-	public static boolean isSupported() {
-		initialize();
-		return supported;
-	}
-
-	static Object install( JRootPane rootPane ) {
-		if( !isSupported() )
-			return null;
-
-		// check whether root pane already has a parent, which is the case when switching LaF
-		Container parent = rootPane.getParent();
-		if( parent != null ) {
-			if( parent instanceof Window )
-				FlatNativeWindowBorder.install( (Window) parent );
-			return null;
-		}
-
-		// Use hierarchy listener to wait until the root pane is added to a window.
-		// Enabling JBR decorations must be done very early, probably before
-		// window becomes displayable (window.isDisplayable()). Tried also using
-		// "ancestor" property change event on root pane, but this is invoked too late.
-		HierarchyListener addListener = new HierarchyListener() {
-			@Override
-			public void hierarchyChanged( HierarchyEvent e ) {
-				if( e.getChanged() != rootPane || (e.getChangeFlags() & HierarchyEvent.PARENT_CHANGED) == 0 )
-					return;
-
-				Container parent = e.getChangedParent();
-				if( parent instanceof Window )
-					FlatNativeWindowBorder.install( (Window) parent );
-
-				// remove listener since it is actually not possible to uninstall JBR decorations
-				// use invokeLater to remove listener to avoid that listener
-				// is removed while listener queue is processed
-				EventQueue.invokeLater( () -> {
-					rootPane.removeHierarchyListener( this );
-				} );
-			}
-		};
-		rootPane.addHierarchyListener( addListener );
-		return addListener;
-	}
-
-	static void uninstall( JRootPane rootPane, Object data ) {
-		// remove listener (if not yet done)
-		if( data instanceof HierarchyListener )
-			rootPane.removeHierarchyListener( (HierarchyListener) data );
-
-		// since it is actually not possible to uninstall JBR decorations,
-		// simply reduce titleBarHeight so that it is still possible to resize window
-		// and remove hitTestSpots
-		Container parent = rootPane.getParent();
-		if( parent instanceof Window )
-			setHasCustomDecoration( (Window) parent, false );
-	}
-
-	static boolean hasCustomDecoration( Window window ) {
-		if( !isSupported() )
-			return false;
-
-		try {
-			return (Boolean) Window_hasCustomDecoration.invoke( window );
-		} catch( Exception ex ) {
-			LoggingFacade.INSTANCE.logSevere( null, ex );
-			return false;
-		}
-	}
-
-	static void setHasCustomDecoration( Window window, boolean hasCustomDecoration ) {
-		if( !isSupported() )
-			return;
-
-		try {
-			if( hasCustomDecoration )
-				Window_setHasCustomDecoration.invoke( window );
-			else
-				setTitleBarHeightAndHitTestSpots( window, 4, Collections.emptyList() );
-		} catch( Exception ex ) {
-			LoggingFacade.INSTANCE.logSevere( null, ex );
-		}
-	}
-
-	static void setTitleBarHeightAndHitTestSpots( Window window, int titleBarHeight, List<Rectangle> hitTestSpots ) {
-		if( !isSupported() )
-			return;
-
-		try {
-			Object compAccessor = AWTAccessor_getComponentAccessor.invoke( null );
-			Object peer = AWTAccessor_ComponentAccessor_getPeer.invoke( compAccessor, window );
-			WWindowPeer_setCustomDecorationTitleBarHeight.invoke( peer, titleBarHeight );
-			WWindowPeer_setCustomDecorationHitTestSpots.invoke( peer, hitTestSpots );
-		} catch( Exception ex ) {
-			LoggingFacade.INSTANCE.logSevere( null, ex );
-		}
-	}
-
-	private static void initialize() {
-		if( supported != null )
-			return;
-		supported = false;
-
-		// requires JetBrains Runtime 11 and Windows 10
-		if( !SystemInfo.isJetBrainsJVM_11_orLater || !SystemInfo.isWindows_10_orLater )
-			return;
-
-		try {
-			Class<?> awtAcessorClass = Class.forName( "sun.awt.AWTAccessor" );
-			Class<?> compAccessorClass = Class.forName( "sun.awt.AWTAccessor$ComponentAccessor" );
-			AWTAccessor_getComponentAccessor = awtAcessorClass.getDeclaredMethod( "getComponentAccessor" );
-			AWTAccessor_ComponentAccessor_getPeer = compAccessorClass.getDeclaredMethod( "getPeer", Component.class );
-
-			Class<?> peerClass = Class.forName( "sun.awt.windows.WWindowPeer" );
-			WWindowPeer_setCustomDecorationTitleBarHeight = peerClass.getDeclaredMethod( "setCustomDecorationTitleBarHeight", int.class );
-			WWindowPeer_setCustomDecorationHitTestSpots = peerClass.getDeclaredMethod( "setCustomDecorationHitTestSpots", List.class );
-			WWindowPeer_setCustomDecorationTitleBarHeight.setAccessible( true );
-			WWindowPeer_setCustomDecorationHitTestSpots.setAccessible( true );
-
-			Window_hasCustomDecoration = Window.class.getDeclaredMethod( "hasCustomDecoration" );
-			Window_setHasCustomDecoration = Window.class.getDeclaredMethod( "setHasCustomDecoration" );
-			Window_hasCustomDecoration.setAccessible( true );
-			Window_setHasCustomDecoration.setAccessible( true );
-
-			supported = true;
-		} catch( Exception ex ) {
-			// ignore
-		}
-	}
-
-	//---- class JBRWindowTopBorder -------------------------------------------
-
-	static class JBRWindowTopBorder
-		extends BorderUIResource.EmptyBorderUIResource
-	{
-		private static JBRWindowTopBorder instance;
-
-		private final Color activeLightColor = new Color( 0x707070 );
-		private final Color activeDarkColor = new Color( 0x2D2E2F );
-		private final Color inactiveLightColor = new Color( 0xaaaaaa );
-		private final Color inactiveDarkColor = new Color( 0x494A4B );
-
-		private boolean colorizationAffectsBorders;
-		private Color activeColor;
-
-		static JBRWindowTopBorder getInstance() {
-			if( instance == null )
-				instance = new JBRWindowTopBorder();
-			return instance;
-		}
-
-        JBRWindowTopBorder() {
-			super( 1, 0, 0, 0 );
-
-			update();
-			installListeners();
-        }
-
-        void update() {
-			colorizationAffectsBorders = isColorizationColorAffectsBorders();
-			activeColor = calculateActiveBorderColor();
-        }
-
-        void installListeners() {
-			Toolkit toolkit = Toolkit.getDefaultToolkit();
-			toolkit.addPropertyChangeListener( "win.dwm.colorizationColor.affects.borders", e -> {
-				colorizationAffectsBorders = isColorizationColorAffectsBorders();
-				activeColor = calculateActiveBorderColor();
-			} );
-
-			PropertyChangeListener l = e -> {
-				activeColor = calculateActiveBorderColor();
-			};
-			toolkit.addPropertyChangeListener( "win.dwm.colorizationColor", l );
-			toolkit.addPropertyChangeListener( "win.dwm.colorizationColorBalance", l );
-			toolkit.addPropertyChangeListener( "win.frame.activeBorderColor", l );
-		}
-
-        boolean isColorizationColorAffectsBorders() {
-			Object value = Toolkit.getDefaultToolkit().getDesktopProperty( "win.dwm.colorizationColor.affects.borders" );
-			return (value instanceof Boolean) ? (Boolean) value : true;
-		}
-
-        Color getColorizationColor() {
-			return (Color) Toolkit.getDefaultToolkit().getDesktopProperty( "win.dwm.colorizationColor" );
-        }
-
-        int getColorizationColorBalance() {
-			Object value = Toolkit.getDefaultToolkit().getDesktopProperty( "win.dwm.colorizationColorBalance" );
-			return (value instanceof Integer) ? (Integer) value : -1;
-        }
-
-		private Color calculateActiveBorderColor() {
-			if( !colorizationAffectsBorders )
-				return null;
-
-			Color colorizationColor = getColorizationColor();
-			if( colorizationColor != null ) {
-				int colorizationColorBalance = getColorizationColorBalance();
-				if( colorizationColorBalance < 0 || colorizationColorBalance > 100 )
-					colorizationColorBalance = 100;
-
-				if( colorizationColorBalance == 0 )
-					return new Color( 0xD9D9D9 );
-				if( colorizationColorBalance == 100 )
-					return colorizationColor;
-
-				float alpha = colorizationColorBalance / 100.0f;
-				float remainder = 1 - alpha;
-				int r = Math.round( colorizationColor.getRed() * alpha + 0xD9 * remainder );
-				int g = Math.round( colorizationColor.getGreen() * alpha + 0xD9 * remainder );
-				int b = Math.round( colorizationColor.getBlue() * alpha + 0xD9 * remainder );
-
-				// avoid potential IllegalArgumentException in Color constructor
-				r = Math.min( Math.max( r, 0 ), 255 );
-				g = Math.min( Math.max( g, 0 ), 255 );
-				b = Math.min( Math.max( b, 0 ), 255 );
-
-				return new Color( r, g, b );
-			}
-
-			Color activeBorderColor = (Color) Toolkit.getDefaultToolkit().getDesktopProperty( "win.frame.activeBorderColor" );
-			return (activeBorderColor != null) ? activeBorderColor : UIManager.getColor( "MenuBar.borderColor" );
-		}
-
-		@Override
-		public void paintBorder( Component c, Graphics g, int x, int y, int width, int height ) {
-			Window window = SwingUtilities.windowForComponent( c );
-			boolean active = window != null && window.isActive();
-			boolean dark = FlatLaf.isLafDark();
-
-			g.setColor( active
-				? (activeColor != null ? activeColor : (dark ? activeDarkColor : activeLightColor))
-				: (dark ? inactiveDarkColor : inactiveLightColor) );
-			HiDPIUtils.paintAtScale1x( (Graphics2D) g, x, y, width, height, this::paintImpl );
-		}
-
-		private void paintImpl( Graphics2D g, int x, int y, int width, int height, double scaleFactor ) {
-			g.fillRect( x, y, width, 1 );
-		}
-
-		void repaintBorder( Component c ) {
-			c.repaint( 0, 0, c.getWidth(), 1 );
-		}
-	}
-}

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/JavaCompatibility2.java

@@ -0,0 +1,153 @@
+/*
+ * Copyright 2024 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.formdev.flatlaf.ui;
+
+import java.io.File;
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import java.lang.reflect.Method;
+import javax.swing.JComponent;
+import javax.swing.JList;
+import javax.swing.JPanel;
+import javax.swing.JTable;
+import javax.swing.JTree;
+import javax.swing.filechooser.FileSystemView;
+import javax.swing.plaf.ComponentUI;
+import javax.swing.text.JTextComponent;
+import com.formdev.flatlaf.util.LoggingFacade;
+import com.formdev.flatlaf.util.SystemInfo;
+
+/**
+ * Provides Java version compatibility methods.
+ * <p>
+ * WARNING: This is private API and may change.
+ *
+ * @author Karl Tauber
+ * @since 3.3
+ */
+public class JavaCompatibility2
+{
+	private static boolean getUIMethodInitialized;
+	private static MethodHandle getUIMethod;
+
+	/**
+	 * Java 8: getUI() method on various components (e.g. JButton, JList, etc)
+	 * <br>
+	 * Java 9: javax.swing.JComponent.getUI()
+	 */
+	public static ComponentUI getUI( JComponent c ) {
+		try {
+			// Java 9+
+			if( SystemInfo.isJava_9_orLater ) {
+				if( !getUIMethodInitialized ) {
+					getUIMethodInitialized = true;
+
+					try {
+						MethodType mt = MethodType.methodType( ComponentUI.class, new Class[0] );
+						getUIMethod = MethodHandles.publicLookup().findVirtual( JComponent.class, "getUI", mt );
+					} catch( Exception ex ) {
+						// ignore
+						LoggingFacade.INSTANCE.logSevere( null, ex );
+					}
+				}
+
+				if( getUIMethod != null )
+					return (ComponentUI) getUIMethod.invoke( c );
+			}
+
+			// components often used (e.g. as view in scroll panes)
+			if( c instanceof JPanel )
+				return ((JPanel)c).getUI();
+			if( c instanceof JList )
+				return ((JList<?>)c).getUI();
+			if( c instanceof JTable )
+				return ((JTable)c).getUI();
+			if( c instanceof JTree )
+				return ((JTree)c).getUI();
+			if( c instanceof JTextComponent )
+				return ((JTextComponent)c).getUI();
+
+			// Java 8 and fallback
+			Method m = c.getClass().getMethod( "getUI" );
+			return (ComponentUI) m.invoke( c );
+		} catch( Throwable ex ) {
+			// ignore
+			return null;
+		}
+	}
+
+	/**
+	 * Java 8 - 11 on Windows: sun.awt.shell.ShellFolder.get( "fileChooserShortcutPanelFolders" )
+	 * <br>
+	 * Java 12: javax.swing.filechooser.FileSystemView.getChooserShortcutPanelFiles()
+	 *
+	 * @since 3.4
+	 */
+	public static File[] getChooserShortcutPanelFiles( FileSystemView fsv ) {
+		try {
+			if( SystemInfo.isJava_12_orLater ) {
+				Method m = fsv.getClass().getMethod( "getChooserShortcutPanelFiles" );
+				File[] files = (File[]) m.invoke( fsv );
+
+				// on macOS and Linux, files consists only of the user home directory
+				if( files.length == 1 && files[0].equals( new File( System.getProperty( "user.home" ) ) ) )
+					files = new File[0];
+
+				return files;
+			} else if( SystemInfo.isWindows ) {
+				Class<?> cls = Class.forName( "sun.awt.shell.ShellFolder" );
+				Method m = cls.getMethod( "get", String.class );
+				return (File[]) m.invoke( null, "fileChooserShortcutPanelFolders" );
+			}
+		} catch( IllegalAccessException ex ) {
+			// do not log because access may be denied via VM option '--illegal-access=deny'
+		} catch( Exception ex ) {
+			LoggingFacade.INSTANCE.logSevere( null, ex );
+		}
+
+		// fallback
+		return new File[0];
+	}
+
+	/**
+	 * Java 8: sun.awt.shell.ShellFolder.get( "fileChooserComboBoxFolders" )
+	 * <br>
+	 * Java 9: javax.swing.filechooser.FileSystemView.getChooserComboBoxFiles()
+	 *
+	 * @since 3.4
+	 */
+	public static File[] getChooserComboBoxFiles( FileSystemView fsv ) {
+		try {
+			if( SystemInfo.isJava_9_orLater ) {
+				Method m = fsv.getClass().getMethod( "getChooserComboBoxFiles" );
+				return (File[]) m.invoke( fsv );
+			} else {
+				Class<?> cls = Class.forName( "sun.awt.shell.ShellFolder" );
+				Method m = cls.getMethod( "get", String.class );
+				return (File[]) m.invoke( null, "fileChooserComboBoxFolders" );
+			}
+		} catch( IllegalAccessException ex ) {
+			// do not log because access may be denied via VM option '--illegal-access=deny'
+		} catch( Exception ex ) {
+			LoggingFacade.INSTANCE.logSevere( null, ex );
+		}
+
+		// fallback
+		return new File[0];
+	}
+}

flatlaf-core/src/main/java/com/formdev/flatlaf/util/FontUtils.java

@@ -80,7 +80,7 @@ public class FontUtils
 
 	/**
 	 * Loads a font family previously registered via {@link #registerFontFamilyLoader(String, Runnable)}.
-	 * If the family is already loaded or no londer is registered for that family, nothing happens.
+	 * If the family is already loaded or no loader is registered for that family, nothing happens.
 	 */
 	public static void loadFontFamily( String family ) {
 		if( !hasLoaders() )
@@ -109,7 +109,7 @@ public class FontUtils
 	}
 
 	/**
-	 * Returns all font familiy names available in the graphics environment.
+	 * Returns all font family names available in the graphics environment.
 	 * This invokes {@link GraphicsEnvironment#getAvailableFontFamilyNames()} and
 	 * appends families registered for lazy loading via {@link #registerFontFamilyLoader(String, Runnable)}
 	 * to the result.

flatlaf-core/src/main/java/com/formdev/flatlaf/util/HiDPIUtils.java

@@ -192,7 +192,8 @@ public class HiDPIUtils
 
 				case "Inter":
 				case "Inter Light":
-				case "Inter Semi Bold":
+				case "Inter Semi Bold":	// Inter v3
+				case "Inter SemiBold":	// Inter v4
 				case "Roboto":
 				case "Roboto Light":
 				case "Roboto Medium":

flatlaf-core/src/main/java/com/formdev/flatlaf/util/NativeLibrary.java

@@ -116,7 +116,11 @@ public class NativeLibrary
 		try {
 			// for development environment
 			if( "file".equals( libraryUrl.getProtocol() ) ) {
-				File libraryFile = new File( libraryUrl.getPath() );
+				String binPath = libraryUrl.getPath();
+				String srcPath = binPath.replace( "flatlaf-core/bin/main/", "flatlaf-core/src/main/resources/" );
+				File libraryFile = new File( srcPath ); // use from 'src' folder if available
+				if( !libraryFile.isFile() )
+					libraryFile = new File( binPath ); // use from 'bin' or 'output' folder if available
 				if( libraryFile.isFile() ) {
 					// load library without copying
 					System.load( libraryFile.getCanonicalPath() );

flatlaf-core/src/main/java/com/formdev/flatlaf/util/UIScale.java

@@ -204,7 +204,7 @@ public class UIScale
 		if( SystemInfo.isWindows ) {
 			// Special handling for Windows to be compatible with OS scaling,
 			// which distinguish between "screen scaling" and "text scaling".
-			//  - Windows "screen scaling" scales everything (text, icon, gaps, etc)
+			//  - Windows "screen scaling" scales everything (text, icon, gaps, etc.)
 			//    and may have different scaling factors for each screen.
 			//  - Windows "text scaling" increases only the font size, but on all screens.
 			//

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatDarkLaf.properties

@@ -246,6 +246,7 @@ PasswordField.revealIconColor = @foreground
 
 #---- Popup ----
 
+[mac]Popup.roundedBorderWidth = 1
 Popup.dropShadowColor = #000
 Popup.dropShadowOpacity = 0.25
 

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatLaf.properties

@@ -289,6 +289,7 @@ ComboBox.popupInsets = 0,0,0,0
 ComboBox.selectionInsets = 0,0,0,0
 ComboBox.selectionArc = 0
 ComboBox.borderCornerRadius = $Popup.borderCornerRadius
+[mac]ComboBox.roundedBorderWidth = $Popup.roundedBorderWidth
 
 
 #---- Component ----
@@ -505,6 +506,7 @@ PasswordField.revealIcon = com.formdev.flatlaf.icons.FlatRevealIcon
 #---- Popup ----
 
 Popup.borderCornerRadius = 4
+[mac]Popup.roundedBorderWidth = 0
 Popup.dropShadowPainted = true
 Popup.dropShadowInsets = -4,-4,4,4
 
@@ -514,6 +516,7 @@ Popup.dropShadowInsets = -4,-4,4,4
 PopupMenu.border = com.formdev.flatlaf.ui.FlatPopupMenuBorder
 PopupMenu.borderInsets = 4,1,4,1
 PopupMenu.borderCornerRadius = $Popup.borderCornerRadius
+[mac]PopupMenu.roundedBorderWidth = $Popup.roundedBorderWidth
 PopupMenu.background = @menuBackground
 PopupMenu.scrollArrowColor = @buttonArrowColor
 
@@ -597,10 +600,15 @@ ScrollBar.allowsAbsolutePositioning = true
 
 #---- ScrollPane ----
 
-ScrollPane.border = com.formdev.flatlaf.ui.FlatBorder
+ScrollPane.border = com.formdev.flatlaf.ui.FlatScrollPaneBorder
 ScrollPane.background = $ScrollBar.track
 ScrollPane.fillUpperCorner = true
 ScrollPane.smoothScrolling = true
+ScrollPane.arc = 0
+#ScrollPane.List.arc = -1
+#ScrollPane.Table.arc = -1
+#ScrollPane.TextComponent.arc = -1
+#ScrollPane.Tree.arc = -1
 
 
 #---- SearchField ----
@@ -697,6 +705,8 @@ TabbedPane.tabAreaAlignment = leading
 TabbedPane.tabAlignment = center
 # allowed values: preferred, equal or compact
 TabbedPane.tabWidthMode = preferred
+# allowed values: none, auto, left or right
+TabbedPane.tabRotation = none
 
 # allowed values: underlined or card
 TabbedPane.tabType = underlined
@@ -729,9 +739,11 @@ Table.rowHeight = 20
 Table.showHorizontalLines = false
 Table.showVerticalLines = false
 Table.showTrailingVerticalLine = false
+Table.paintOutsideAlternateRows = false
+Table.editorSelectAllOnStartEditing = true
 Table.consistentHomeEndKeyBehavior = true
 Table.intercellSpacing = 0,0
-Table.scrollPaneBorder = com.formdev.flatlaf.ui.FlatBorder
+Table.scrollPaneBorder = com.formdev.flatlaf.ui.FlatScrollPaneBorder
 Table.ascendingSortIcon = com.formdev.flatlaf.icons.FlatAscendingSortIcon
 Table.descendingSortIcon = com.formdev.flatlaf.icons.FlatDescendingSortIcon
 Table.sortIconColor = @icon
@@ -819,7 +831,6 @@ TitlePane.centerTitleIfMenuBarEmbedded = true
 TitlePane.showIconBesideTitle = false
 TitlePane.menuBarTitleGap = 40
 TitlePane.menuBarTitleMinimumGap = 12
-TitlePane.menuBarResizeHeight = 4
 TitlePane.closeIcon = com.formdev.flatlaf.icons.FlatWindowCloseIcon
 TitlePane.iconifyIcon = com.formdev.flatlaf.icons.FlatWindowIconifyIcon
 TitlePane.maximizeIcon = com.formdev.flatlaf.icons.FlatWindowMaximizeIcon
@@ -902,6 +913,7 @@ ToolTipManager.enableToolTipMode = activeApplication
 #---- ToolTip ----
 
 ToolTip.borderCornerRadius = $Popup.borderCornerRadius
+[mac]ToolTip.roundedBorderWidth = $Popup.roundedBorderWidth
 
 
 #---- Tree ----

flatlaf-core/src/main/resources/com/formdev/flatlaf/themes/FlatMacDarkLaf.properties

@@ -295,3 +295,8 @@ ToggleButton.disabledBackground = $Button.disabledBackground
 ToggleButton.selectedBackground = lighten($ToggleButton.background,20%,derived)
 
 ToggleButton.toolbar.selectedBackground = #fff3
+
+
+#---- ToolBar ----
+
+ToolBar.hoverButtonGroupArc = 14

flatlaf-core/src/main/resources/com/formdev/flatlaf/themes/FlatMacLightLaf.properties

@@ -291,3 +291,8 @@ TextPane.selectionForeground = @textSelectionForeground
 #---- ToggleButton ----
 
 ToggleButton.disabledBackground = $Button.disabledBackground
+
+
+#---- ToolBar ----
+
+ToolBar.hoverButtonGroupArc = 14

flatlaf-core/src/test/java/com/formdev/flatlaf/ui/TestFlatStyleableInfo.java

@@ -601,7 +601,7 @@ public class TestFlatStyleableInfo
 		);
 
 		// border
-		flatBorder( expected );
+		flatScrollPaneBorder( expected );
 
 		assertMapEquals( expected, ui.getStyleableInfos( c ) );
 	}
@@ -689,6 +689,9 @@ public class TestFlatStyleableInfo
 
 		Map<String, Class<?>> expected = expectedMap(
 			"arrowType", String.class,
+			"draggingColor", Color.class,
+			"hoverColor", Color.class,
+			"pressedColor", Color.class,
 			"oneTouchArrowColor", Color.class,
 			"oneTouchHoverArrowColor", Color.class,
 			"oneTouchPressedArrowColor", Color.class,
@@ -752,6 +755,7 @@ public class TestFlatStyleableInfo
 			"tabAreaAlignment", String.class,
 			"tabAlignment", String.class,
 			"tabWidthMode", String.class,
+			"tabRotation", String.class,
 
 			"arrowType", String.class,
 			"buttonInsets", Insets.class,
@@ -925,7 +929,10 @@ public class TestFlatStyleableInfo
 			"hoverButtonGroupBackground", Color.class,
 
 			"borderMargins", Insets.class,
-			"gripColor", Color.class
+			"gripColor", Color.class,
+
+			"separatorWidth", Integer.class,
+			"separatorColor", Color.class
 		);
 
 		assertMapEquals( expected, ui.getStyleableInfos( c ) );
@@ -1005,17 +1012,23 @@ public class TestFlatStyleableInfo
 
 		expectedMap( expected,
 			"arc", int.class,
-
 			"roundRect", Boolean.class
 		);
 	}
 
+	private void flatScrollPaneBorder( Map<String, Class<?>> expected ) {
+		flatBorder( expected );
+
+		expectedMap( expected,
+			"arc", int.class
+		);
+	}
+
 	private void flatTextBorder( Map<String, Class<?>> expected ) {
 		flatBorder( expected );
 
 		expectedMap( expected,
 			"arc", int.class,
-
 			"roundRect", Boolean.class
 		);
 	}

flatlaf-core/src/test/java/com/formdev/flatlaf/ui/TestFlatStyleableValue.java

@@ -625,7 +625,7 @@ public class TestFlatStyleableValue
 		FlatScrollPaneUI ui = (FlatScrollPaneUI) c.getUI();
 
 		// border
-		flatBorder( c, ui );
+		flatScrollPaneBorder( c, ui );
 
 		testBoolean( c, ui, "showButtons", true );
 	}
@@ -699,6 +699,9 @@ public class TestFlatStyleableValue
 		FlatSplitPaneUI ui = (FlatSplitPaneUI) c.getUI();
 
 		testString( c, ui, "arrowType", "chevron" );
+		testColor( c, ui, "draggingColor", 0x123456 );
+		testColor( c, ui, "hoverColor", 0x123456 );
+		testColor( c, ui, "pressedColor", 0x123456 );
 		testColor( c, ui, "oneTouchArrowColor", 0x123456 );
 		testColor( c, ui, "oneTouchHoverArrowColor", 0x123456 );
 		testColor( c, ui, "oneTouchPressedArrowColor", 0x123456 );
@@ -758,6 +761,7 @@ public class TestFlatStyleableValue
 		testString( c, ui, "tabAreaAlignment", "leading" );
 		testString( c, ui, "tabAlignment", "center" );
 		testString( c, ui, "tabWidthMode", "preferred" );
+		testString( c, ui, "tabRotation", "none" );
 
 		testString( c, ui, "arrowType", "chevron" );
 		testInsets( c, ui, "buttonInsets", 1,2,3,4 );
@@ -902,6 +906,9 @@ public class TestFlatStyleableValue
 
 		testInsets( c, ui, "borderMargins", 1,2,3,4 );
 		testColor( c, ui, "gripColor", 0x123456 );
+
+		testInteger( c, ui, "separatorWidth", 123 );
+		testColor( c, ui, "separatorColor", 0x123456 );
 	}
 
 	@Test
@@ -965,15 +972,19 @@ public class TestFlatStyleableValue
 		flatBorder( c, ui );
 
 		testInteger( c, ui, "arc", 123 );
-
 		testBoolean( c, ui, "roundRect", true );
 	}
 
+	private void flatScrollPaneBorder( JComponent c, StyleableUI ui ) {
+		flatBorder( c, ui );
+
+		testInteger( c, ui, "arc", 123 );
+	}
+
 	private void flatTextBorder( JComponent c, StyleableUI ui ) {
 		flatBorder( c, ui );
 
 		testInteger( c, ui, "arc", 123 );
-
 		testBoolean( c, ui, "roundRect", true );
 	}
 
@@ -1034,6 +1045,17 @@ public class TestFlatStyleableValue
 		// FlatRoundBorder extends FlatBorder
 		flatBorder( border );
 
+		testValue( border, "arc", 6 );
+		testValue( border, "roundRect", true );
+	}
+
+	@Test
+	void flatScrollPaneBorder() {
+		FlatScrollPaneBorder border = new FlatScrollPaneBorder();
+
+		// FlatScrollPaneBorder extends FlatBorder
+		flatBorder( border );
+
 		testValue( border, "arc", 6 );
 	}
 
@@ -1045,6 +1067,7 @@ public class TestFlatStyleableValue
 		flatBorder( border );
 
 		testValue( border, "arc", 6 );
+		testValue( border, "roundRect", true );
 	}
 
 	@Test

flatlaf-core/src/test/java/com/formdev/flatlaf/ui/TestFlatStyling.java

@@ -760,7 +760,7 @@ public class TestFlatStyling
 		FlatScrollPaneUI ui = (FlatScrollPaneUI) c.getUI();
 
 		// border
-		flatBorder( style -> ui.applyStyle( style ) );
+		flatScrollPaneBorder( style -> ui.applyStyle( style ) );
 
 		ui.applyStyle( "showButtons: true" );
 
@@ -870,6 +870,9 @@ public class TestFlatStyling
 		FlatSplitPaneUI ui = (FlatSplitPaneUI) c.getUI();
 
 		ui.applyStyle( "arrowType: chevron" );
+		ui.applyStyle( "draggingColor: #fff" );
+		ui.applyStyle( "hoverColor: #fff" );
+		ui.applyStyle( "pressedColor: #fff" );
 		ui.applyStyle( "oneTouchArrowColor: #fff" );
 		ui.applyStyle( "oneTouchHoverArrowColor: #fff" );
 		ui.applyStyle( "oneTouchPressedArrowColor: #fff" );
@@ -937,6 +940,7 @@ public class TestFlatStyling
 		ui.applyStyle( "tabAreaAlignment: leading" );
 		ui.applyStyle( "tabAlignment: center" );
 		ui.applyStyle( "tabWidthMode: preferred" );
+		ui.applyStyle( "tabRotation: none" );
 
 		ui.applyStyle( "arrowType: chevron" );
 		ui.applyStyle( "buttonInsets: 1,2,3,4" );
@@ -1146,6 +1150,9 @@ public class TestFlatStyling
 		ui.applyStyle( "borderMargins: 1,2,3,4" );
 		ui.applyStyle( "gripColor: #fff" );
 
+		ui.applyStyle( "separatorWidth: 6" );
+		ui.applyStyle( "separatorColor: #fff" );
+
 		// JComponent properties
 		ui.applyStyle( "background: #fff" );
 		ui.applyStyle( "foreground: #fff" );
@@ -1234,15 +1241,19 @@ public class TestFlatStyling
 		flatBorder( applyStyle );
 
 		applyStyle.accept( "arc: 6" );
-
 		applyStyle.accept( "roundRect: true" );
 	}
 
+	private void flatScrollPaneBorder( Consumer<String> applyStyle ) {
+		flatBorder( applyStyle );
+
+		applyStyle.accept( "arc: 6" );
+	}
+
 	private void flatTextBorder( Consumer<String> applyStyle ) {
 		flatBorder( applyStyle );
 
 		applyStyle.accept( "arc: 6" );
-
 		applyStyle.accept( "roundRect: true" );
 	}
 

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/ControlBar.java

@@ -28,6 +28,8 @@ import javax.swing.plaf.metal.MetalLookAndFeel;
 import javax.swing.plaf.nimbus.NimbusLookAndFeel;
 import com.formdev.flatlaf.*;
 import com.formdev.flatlaf.extras.FlatAnimatedLafChange;
+import com.formdev.flatlaf.themes.FlatMacDarkLaf;
+import com.formdev.flatlaf.themes.FlatMacLightLaf;
 import com.formdev.flatlaf.util.LoggingFacade;
 import com.formdev.flatlaf.util.SystemInfo;
 import com.formdev.flatlaf.util.UIScale;
@@ -66,6 +68,8 @@ class ControlBar
 		lafModel.addElement( new LookAndFeelInfo( "FlatLaf Dark (F2)", FlatDarkLaf.class.getName() ) );
 		lafModel.addElement( new LookAndFeelInfo( "FlatLaf IntelliJ (F3)", FlatIntelliJLaf.class.getName() ) );
 		lafModel.addElement( new LookAndFeelInfo( "FlatLaf Darcula (F4)", FlatDarculaLaf.class.getName() ) );
+		lafModel.addElement( new LookAndFeelInfo( "FlatLaf macOS Light (F5)", FlatMacLightLaf.class.getName() ) );
+		lafModel.addElement( new LookAndFeelInfo( "FlatLaf macOS Dark (F6)", FlatMacDarkLaf.class.getName() ) );
 
 		UIManager.LookAndFeelInfo[] lookAndFeels = UIManager.getInstalledLookAndFeels();
 		for( UIManager.LookAndFeelInfo lookAndFeel : lookAndFeels ) {
@@ -127,6 +131,8 @@ class ControlBar
 		registerSwitchToLookAndFeel( KeyEvent.VK_F2, FlatDarkLaf.class.getName() );
 		registerSwitchToLookAndFeel( KeyEvent.VK_F3, FlatIntelliJLaf.class.getName() );
 		registerSwitchToLookAndFeel( KeyEvent.VK_F4, FlatDarculaLaf.class.getName() );
+		registerSwitchToLookAndFeel( KeyEvent.VK_F5, FlatMacLightLaf.class.getName() );
+		registerSwitchToLookAndFeel( KeyEvent.VK_F6, FlatMacDarkLaf.class.getName() );
 
 		if( SystemInfo.isWindows )
 			registerSwitchToLookAndFeel( KeyEvent.VK_F9, "com.sun.java.swing.plaf.windows.WindowsLookAndFeel" );

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/DataComponentsPanel.java

@@ -18,7 +18,6 @@ package com.formdev.flatlaf.demo;
 
 import java.awt.Color;
 import java.awt.Dimension;
-import java.awt.EventQueue;
 import java.awt.datatransfer.DataFlavor;
 import java.awt.datatransfer.StringSelection;
 import java.awt.datatransfer.Transferable;
@@ -116,15 +115,16 @@ class DataComponentsPanel
 		table1.setGridColor( redGridColorCheckBox.isSelected() ? Color.red : UIManager.getColor( "Table.gridColor" ) );
 	}
 
-	@Override
-	public void updateUI() {
-		super.updateUI();
+	private void showHorizontalLinesPropertyChange() {
+		showHorizontalLinesCheckBox.setSelected( table1.getShowHorizontalLines() );
+	}
 
-		EventQueue.invokeLater( () -> {
-			showHorizontalLinesChanged();
-			showVerticalLinesChanged();
-			intercellSpacingChanged();
-		} );
+	private void showVerticalLinesPropertyChange() {
+		showVerticalLinesCheckBox.setSelected( table1.getShowVerticalLines() );
+	}
+
+	private void intercellSpacingPropertyChange() {
+		intercellSpacingCheckBox.setSelected( table1.getRowMargin() != 0 );
 	}
 
 	@SuppressWarnings( { "unchecked", "rawtypes" } )
@@ -333,10 +333,10 @@ class DataComponentsPanel
 					"Not editable", "Text", "Combo", "Combo Editable", "Integer", "Boolean"
 				}
 			) {
-				Class<?>[] columnTypes = new Class<?>[] {
+				Class<?>[] columnTypes = {
 					Object.class, Object.class, String.class, String.class, Integer.class, Boolean.class
 				};
-				boolean[] columnEditable = new boolean[] {
+				boolean[] columnEditable = {
 					false, true, true, true, true, true
 				};
 				@Override
@@ -383,6 +383,9 @@ class DataComponentsPanel
 			}
 			table1.setAutoCreateRowSorter(true);
 			table1.setComponentPopupMenu(popupMenu2);
+			table1.addPropertyChangeListener("showHorizontalLines", e -> showHorizontalLinesPropertyChange());
+			table1.addPropertyChangeListener("showVerticalLines", e -> showVerticalLinesPropertyChange());
+			table1.addPropertyChangeListener("rowMargin", e -> intercellSpacingPropertyChange());
 			scrollPane5.setViewportView(table1);
 		}
 		add(scrollPane5, "cell 1 3 3 1,width 300");

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/DataComponentsPanel.jfd

@@ -1,4 +1,4 @@
-JFDML JFormDesigner: "8.0.0.0.194" Java: "17.0.2" encoding: "UTF-8"
+JFDML JFormDesigner: "8.2.0.0.331" Java: "21" encoding: "UTF-8"
 
 new FormModel {
 	contentType: "form/swing"
@@ -333,6 +333,9 @@ new FormModel {
 					auxiliary() {
 						"JavaCodeGenerator.variableLocal": false
 					}
+					addEvent( new FormEvent( "java.beans.PropertyChangeListener", "propertyChange", "showHorizontalLinesPropertyChange", false, "showHorizontalLines" ) )
+					addEvent( new FormEvent( "java.beans.PropertyChangeListener", "propertyChange", "showVerticalLinesPropertyChange", false, "showVerticalLines" ) )
+					addEvent( new FormEvent( "java.beans.PropertyChangeListener", "propertyChange", "intercellSpacingPropertyChange", false, "rowMargin" ) )
 				} )
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 				"value": "cell 1 3 3 1,width 300"

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/DemoFrame.java

@@ -46,7 +46,6 @@ import com.formdev.flatlaf.icons.FlatAbstractIcon;
 import com.formdev.flatlaf.themes.FlatMacDarkLaf;
 import com.formdev.flatlaf.themes.FlatMacLightLaf;
 import com.formdev.flatlaf.extras.FlatSVGUtils;
-import com.formdev.flatlaf.ui.JBRCustomDecorations;
 import com.formdev.flatlaf.util.ColorFunctions;
 import com.formdev.flatlaf.util.FontUtils;
 import com.formdev.flatlaf.util.LoggingFacade;
@@ -74,6 +73,7 @@ class DemoFrame
 		initComponents();
 		updateFontMenuItems();
 		initAccentColors();
+		initFullWindowContent();
 		controlBar.initialize( this, tabbedPane );
 
 		setIconImages( FlatSVGUtils.createWindowIconImages( "/com/formdev/flatlaf/demo/FlatLaf.svg" ) );
@@ -90,24 +90,23 @@ class DemoFrame
 			// do not use HTML text in menu items because this is not supported in macOS screen menu
 			htmlMenuItem.setText( "some text" );
 
+			JRootPane rootPane = getRootPane();
 			if( SystemInfo.isMacFullWindowContentSupported ) {
 				// expand window content into window title bar and make title bar transparent
-				getRootPane().putClientProperty( "apple.awt.fullWindowContent", true );
-				getRootPane().putClientProperty( "apple.awt.transparentTitleBar", true );
+				rootPane.putClientProperty( "apple.awt.fullWindowContent", true );
+				rootPane.putClientProperty( "apple.awt.transparentTitleBar", true );
+				rootPane.putClientProperty( FlatClientProperties.MACOS_WINDOW_BUTTONS_SPACING, FlatClientProperties.MACOS_WINDOW_BUTTONS_SPACING_LARGE );
 
 				// hide window title
 				if( SystemInfo.isJava_17_orLater )
-					getRootPane().putClientProperty( "apple.awt.windowTitleVisible", false );
+					rootPane.putClientProperty( "apple.awt.windowTitleVisible", false );
 				else
 					setTitle( null );
-
-				// add gap to left side of toolbar
-				toolBar.add( Box.createHorizontalStrut( 70 ), 0 );
 			}
 
 			// enable full screen mode for this window (for Java 8 - 10; not necessary for Java 11+)
 			if( !SystemInfo.isJava_11_orLater )
-				getRootPane().putClientProperty( "apple.awt.fullscreenable", true );
+				rootPane.putClientProperty( "apple.awt.fullscreenable", true );
 		}
 
 		// integrate into macOS screen menu
@@ -462,9 +461,37 @@ class DemoFrame
 			accentColorButtons[i].setVisible( isAccentColorSupported );
 	}
 
+	private void initFullWindowContent() {
+		if( !supportsFlatLafWindowDecorations() )
+			return;
+
+		// create fullWindowContent mode toggle button
+		Icon expandIcon = new FlatSVGIcon( "com/formdev/flatlaf/demo/icons/expand.svg" );
+		Icon collapseIcon = new FlatSVGIcon( "com/formdev/flatlaf/demo/icons/collapse.svg" );
+		JToggleButton fullWindowContentButton = new JToggleButton( expandIcon );
+		fullWindowContentButton.setToolTipText( "Toggle full window content" );
+		fullWindowContentButton.addActionListener( e -> {
+			boolean fullWindowContent = fullWindowContentButton.isSelected();
+			fullWindowContentButton.setIcon( fullWindowContent ? collapseIcon : expandIcon );
+			menuBar.setVisible( !fullWindowContent );
+			toolBar.setVisible( !fullWindowContent );
+			getRootPane().putClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT, fullWindowContent );
+		} );
+
+		// add fullWindowContent mode toggle button to tabbed pane
+		JToolBar trailingToolBar = new JToolBar();
+		trailingToolBar.add( Box.createGlue() );
+		trailingToolBar.add( fullWindowContentButton );
+		tabbedPane.putClientProperty( FlatClientProperties.TABBED_PANE_TRAILING_COMPONENT, trailingToolBar );
+	}
+
+	private boolean supportsFlatLafWindowDecorations() {
+		return FlatLaf.supportsNativeWindowDecorations() || (SystemInfo.isLinux && JFrame.isDefaultLookAndFeelDecorated());
+	}
+
 	private void initComponents() {
 		// JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
-		JMenuBar menuBar1 = new JMenuBar();
+		menuBar = new JMenuBar();
 		JMenu fileMenu = new JMenu();
 		JMenuItem newMenuItem = new JMenuItem();
 		JMenuItem openMenuItem = new JMenuItem();
@@ -510,6 +537,8 @@ class DemoFrame
 		JMenuItem showUIDefaultsInspectorMenuItem = new JMenuItem();
 		JMenu helpMenu = new JMenu();
 		aboutMenuItem = new JMenuItem();
+		JPanel toolBarPanel = new JPanel();
+		JPanel macFullWindowContentButtonsPlaceholder = new JPanel();
 		toolBar = new JToolBar();
 		JButton backButton = new JButton();
 		JButton forwardButton = new JButton();
@@ -525,8 +554,10 @@ class DemoFrame
 		DataComponentsPanel dataComponentsPanel = new DataComponentsPanel();
 		TabsPanel tabsPanel = new TabsPanel();
 		OptionPanePanel optionPanePanel = new OptionPanePanel();
-		ExtrasPanel extrasPanel1 = new ExtrasPanel();
+		ExtrasPanel extrasPanel = new ExtrasPanel();
 		controlBar = new ControlBar();
+		JPanel themesPanelPanel = new JPanel();
+		JPanel winFullWindowContentButtonsPlaceholder = new JPanel();
 		themesPanel = new IJThemesPanel();
 
 		//======== this ========
@@ -535,7 +566,7 @@ class DemoFrame
 		Container contentPane = getContentPane();
 		contentPane.setLayout(new BorderLayout());
 
-		//======== menuBar1 ========
+		//======== menuBar ========
 		{
 
 			//======== fileMenu ========
@@ -580,7 +611,7 @@ class DemoFrame
 				exitMenuItem.addActionListener(e -> exitActionPerformed());
 				fileMenu.add(exitMenuItem);
 			}
-			menuBar1.add(fileMenu);
+			menuBar.add(fileMenu);
 
 			//======== editMenu ========
 			{
@@ -633,7 +664,7 @@ class DemoFrame
 				deleteMenuItem.addActionListener(e -> menuItemActionPerformed(e));
 				editMenu.add(deleteMenuItem);
 			}
-			menuBar1.add(editMenu);
+			menuBar.add(editMenu);
 
 			//======== viewMenu ========
 			{
@@ -733,7 +764,7 @@ class DemoFrame
 				radioButtonMenuItem3.addActionListener(e -> menuItemActionPerformed(e));
 				viewMenu.add(radioButtonMenuItem3);
 			}
-			menuBar1.add(viewMenu);
+			menuBar.add(viewMenu);
 
 			//======== fontMenu ========
 			{
@@ -757,7 +788,7 @@ class DemoFrame
 				decrFontMenuItem.addActionListener(e -> decrFont());
 				fontMenu.add(decrFontMenuItem);
 			}
-			menuBar1.add(fontMenu);
+			menuBar.add(fontMenu);
 
 			//======== optionsMenu ========
 			{
@@ -809,7 +840,7 @@ class DemoFrame
 				showUIDefaultsInspectorMenuItem.addActionListener(e -> showUIDefaultsInspector());
 				optionsMenu.add(showUIDefaultsInspectorMenuItem);
 			}
-			menuBar1.add(optionsMenu);
+			menuBar.add(optionsMenu);
 
 			//======== helpMenu ========
 			{
@@ -822,9 +853,19 @@ class DemoFrame
 				aboutMenuItem.addActionListener(e -> aboutActionPerformed());
 				helpMenu.add(aboutMenuItem);
 			}
-			menuBar1.add(helpMenu);
+			menuBar.add(helpMenu);
 		}
-		setJMenuBar(menuBar1);
+		setJMenuBar(menuBar);
+
+		//======== toolBarPanel ========
+		{
+			toolBarPanel.setLayout(new BorderLayout());
+
+			//======== macFullWindowContentButtonsPlaceholder ========
+			{
+				macFullWindowContentButtonsPlaceholder.setLayout(new FlowLayout());
+			}
+			toolBarPanel.add(macFullWindowContentButtonsPlaceholder, BorderLayout.WEST);
 
 			//======== toolBar ========
 			{
@@ -869,7 +910,9 @@ class DemoFrame
 				showToggleButton.setIcon(new FlatSVGIcon("com/formdev/flatlaf/demo/icons/show.svg"));
 				toolBar.add(showToggleButton);
 			}
-		contentPane.add(toolBar, BorderLayout.NORTH);
+			toolBarPanel.add(toolBar, BorderLayout.CENTER);
+		}
+		contentPane.add(toolBarPanel, BorderLayout.PAGE_START);
 
 		//======== contentPanel ========
 		{
@@ -889,13 +932,25 @@ class DemoFrame
 				tabbedPane.addTab("Data Components", dataComponentsPanel);
 				tabbedPane.addTab("Tabs", tabsPanel);
 				tabbedPane.addTab("Option Pane", optionPanePanel);
-				tabbedPane.addTab("Extras", extrasPanel1);
+				tabbedPane.addTab("Extras", extrasPanel);
 			}
 			contentPanel.add(tabbedPane, "cell 0 0");
 		}
 		contentPane.add(contentPanel, BorderLayout.CENTER);
-		contentPane.add(controlBar, BorderLayout.SOUTH);
-		contentPane.add(themesPanel, BorderLayout.EAST);
+		contentPane.add(controlBar, BorderLayout.PAGE_END);
+
+		//======== themesPanelPanel ========
+		{
+			themesPanelPanel.setLayout(new BorderLayout());
+
+			//======== winFullWindowContentButtonsPlaceholder ========
+			{
+				winFullWindowContentButtonsPlaceholder.setLayout(new FlowLayout());
+			}
+			themesPanelPanel.add(winFullWindowContentButtonsPlaceholder, BorderLayout.NORTH);
+			themesPanelPanel.add(themesPanel, BorderLayout.CENTER);
+		}
+		contentPane.add(themesPanelPanel, BorderLayout.LINE_END);
 
 		//---- buttonGroup1 ----
 		ButtonGroup buttonGroup1 = new ButtonGroup();
@@ -910,8 +965,8 @@ class DemoFrame
 		usersButton.setButtonType( ButtonType.toolBarButton );
 		usersButton.setFocusable( false );
 		usersButton.addActionListener( e -> JOptionPane.showMessageDialog( null, "Hello User! How are you?", "User", JOptionPane.INFORMATION_MESSAGE ) );
-		menuBar1.add( Box.createGlue() );
-		menuBar1.add( usersButton );
+		menuBar.add( Box.createGlue() );
+		menuBar.add( usersButton );
 
 		cutMenuItem.addActionListener( new DefaultEditorKit.CutAction() );
 		copyMenuItem.addActionListener( new DefaultEditorKit.CopyAction() );
@@ -923,7 +978,7 @@ class DemoFrame
 		for( int i = 1; i <= 100; i++ )
 			scrollingPopupMenu.add( "Item " + i );
 
-		if( FlatLaf.supportsNativeWindowDecorations() || (SystemInfo.isLinux && JFrame.isDefaultLookAndFeelDecorated()) ) {
+		if( supportsFlatLafWindowDecorations() ) {
 			if( SystemInfo.isLinux )
 				unsupported( windowDecorationsCheckBoxMenuItem );
 			else
@@ -931,12 +986,6 @@ class DemoFrame
 			menuBarEmbeddedCheckBoxMenuItem.setSelected( UIManager.getBoolean( "TitlePane.menuBarEmbedded" ) );
 			unifiedTitleBarMenuItem.setSelected( UIManager.getBoolean( "TitlePane.unifiedBackground" ) );
 			showTitleBarIconMenuItem.setSelected( UIManager.getBoolean( "TitlePane.showIcon" ) );
-
-			if( JBRCustomDecorations.isSupported() ) {
-				// If the JetBrains Runtime is used, it forces the use of it's own custom
-				// window decoration, which can not disabled.
-				windowDecorationsCheckBoxMenuItem.setEnabled( false );
-			}
 		} else {
 			unsupported( windowDecorationsCheckBoxMenuItem );
 			unsupported( menuBarEmbeddedCheckBoxMenuItem );
@@ -950,6 +999,17 @@ class DemoFrame
 		if( "false".equals( System.getProperty( "flatlaf.animatedLafChange" ) ) )
 			animatedLafChangeMenuItem.setSelected( false );
 
+
+		// on macOS, panel left to toolBar is a placeholder for title bar buttons in fullWindowContent mode
+		macFullWindowContentButtonsPlaceholder.putClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER, "mac zeroInFullScreen" );
+
+		// on Windows/Linux, panel above themesPanel is a placeholder for title bar buttons in fullWindowContent mode
+		winFullWindowContentButtonsPlaceholder.putClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_PLACEHOLDER, "win" );
+
+		// uncomment this line to see title bar buttons placeholders in fullWindowContent mode
+//		UIManager.put( "FlatLaf.debug.panel.showPlaceholders", true );
+
+
 		// remove contentPanel bottom insets
 		MigLayout layout = (MigLayout) contentPanel.getLayout();
 		LC lc = ConstraintParser.parseLayoutConstraint( (String) layout.getLayoutConstraints() );
@@ -970,6 +1030,7 @@ class DemoFrame
 	}
 
 	// JFormDesigner - Variables declaration - DO NOT MODIFY  //GEN-BEGIN:variables
+	private JMenuBar menuBar;
 	private JMenuItem exitMenuItem;
 	private JMenu scrollingPopupMenu;
 	private JMenuItem htmlMenuItem;

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/DemoFrame.jfd

@@ -1,4 +1,4 @@
-JFDML JFormDesigner: "8.1.0.0.283" Java: "19.0.2" encoding: "UTF-8"
+JFDML JFormDesigner: "8.2.1.0.348" Java: "21.0.1" encoding: "UTF-8"
 
 new FormModel {
 	contentType: "form/swing"
@@ -12,6 +12,13 @@ new FormModel {
 			"defaultCloseOperation": 2
 			"$locationPolicy": 2
 			"$sizePolicy": 2
+			add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class java.awt.BorderLayout ) ) {
+				name: "toolBarPanel"
+				add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class java.awt.FlowLayout ) ) {
+					name: "macFullWindowContentButtonsPlaceholder"
+				}, new FormLayoutConstraints( class java.lang.String ) {
+					"value": "West"
+				} )
 				add( new FormContainer( "javax.swing.JToolBar", new FormLayoutManager( class javax.swing.JToolBar ) ) {
 					name: "toolBar"
 					"margin": new java.awt.Insets( 3, 3, 3, 3 )
@@ -64,7 +71,10 @@ new FormModel {
 						"icon": new com.jformdesigner.model.SwingIcon( 0, "/com/formdev/flatlaf/demo/icons/show.svg" )
 					} )
 				}, new FormLayoutConstraints( class java.lang.String ) {
-				"value": "North"
+					"value": "Center"
+				} )
+			}, new FormLayoutConstraints( class java.lang.String ) {
+				"value": "First"
 			} )
 			add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
 				"$layoutConstraints": "insets dialog,hidemode 3"
@@ -105,7 +115,7 @@ new FormModel {
 						"title": "Option Pane"
 					} )
 					add( new FormComponent( "com.formdev.flatlaf.demo.extras.ExtrasPanel" ) {
-						name: "extrasPanel1"
+						name: "extrasPanel"
 					}, new FormLayoutConstraints( null ) {
 						"title": "Extras"
 					} )
@@ -121,7 +131,14 @@ new FormModel {
 					"JavaCodeGenerator.variableLocal": false
 				}
 			}, new FormLayoutConstraints( class java.lang.String ) {
-				"value": "South"
+				"value": "Last"
+			} )
+			add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class java.awt.BorderLayout ) ) {
+				name: "themesPanelPanel"
+				add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class java.awt.FlowLayout ) ) {
+					name: "winFullWindowContentButtonsPlaceholder"
+				}, new FormLayoutConstraints( class java.lang.String ) {
+					"value": "North"
 				} )
 				add( new FormComponent( "com.formdev.flatlaf.demo.intellijthemes.IJThemesPanel" ) {
 					name: "themesPanel"
@@ -130,10 +147,16 @@ new FormModel {
 						"JavaCodeGenerator.variableModifiers": 0
 					}
 				}, new FormLayoutConstraints( class java.lang.String ) {
-				"value": "East"
+					"value": "Center"
+				} )
+			}, new FormLayoutConstraints( class java.lang.String ) {
+				"value": "After"
 			} )
 			menuBar: new FormContainer( "javax.swing.JMenuBar", new FormLayoutManager( class javax.swing.JMenuBar ) ) {
-				name: "menuBar1"
+				name: "menuBar"
+				auxiliary() {
+					"JavaCodeGenerator.variableLocal": false
+				}
 				add( new FormContainer( "javax.swing.JMenu", new FormLayoutManager( class javax.swing.JMenu ) ) {
 					name: "fileMenu"
 					"text": "File"

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/ScrollablePanel.java

@@ -34,7 +34,7 @@ public class ScrollablePanel
 {
 	@Override
 	public Dimension getPreferredScrollableViewportSize() {
-		return UIScale.scale( new Dimension( 400, 400 ) );
+		return new Dimension( getPreferredSize().width, UIScale.scale( 400 ) );
 	}
 
 	@Override
@@ -49,7 +49,7 @@ public class ScrollablePanel
 
 	@Override
 	public boolean getScrollableTracksViewportWidth() {
-		return false;
+		return true;
 	}
 
 	@Override

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/TabsPanel.java

@@ -204,7 +204,7 @@ class TabsPanel
 	private void closeButtonStyleChanged() {
 		// WARNING:
 		//   Do not use this trick to style individual tabbed panes in own code.
-		//   Instead use one styling for all tabbed panes in your application.
+		//   Instead, use one styling for all tabbed panes in your application.
 		if( circleCloseButton.isSelected() ) {
 			UIManager.put( "TabbedPane.closeArc", 999 );
 			UIManager.put( "TabbedPane.closeCrossFilledSize", 5.5f );
@@ -313,6 +313,14 @@ class TabsPanel
 		putTabbedPanesClientProperty( TABBED_PANE_SHOW_TAB_SEPARATORS, showTabSeparators );
 	}
 
+	private void tabRotationChanged() {
+		String tabRotation = rotationAutoButton.isSelected() ? TABBED_PANE_TAB_ROTATION_AUTO
+			: rotationLeftButton.isSelected() ? TABBED_PANE_TAB_ROTATION_LEFT
+			: rotationRightButton.isSelected() ? TABBED_PANE_TAB_ROTATION_RIGHT
+			: null;
+		putTabbedPanesClientProperty( TABBED_PANE_TAB_ROTATION, tabRotation );
+	}
+
 	private void putTabbedPanesClientProperty( String key, Object value ) {
 		updateTabbedPanesRecur( this, tabbedPane -> tabbedPane.putClientProperty( key, value ) );
 	}
@@ -331,6 +339,8 @@ class TabsPanel
 
 	private void initComponents() {
 		// JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
+		JScrollPane tabsScrollPane = new JScrollPane();
+		ScrollablePanel panel6 = new ScrollablePanel();
 		JPanel panel1 = new JPanel();
 		JLabel tabPlacementLabel = new JLabel();
 		tabPlacementToolBar = new JToolBar();
@@ -397,31 +407,50 @@ class TabsPanel
 		scrollAsNeededSingleButton = new JToggleButton();
 		scrollAsNeededButton = new JToggleButton();
 		scrollNeverButton = new JToggleButton();
-		scrollButtonsPlacementLabel = new JLabel();
-		scrollButtonsPlacementToolBar = new JToolBar();
-		scrollBothButton = new JToggleButton();
-		scrollTrailingButton = new JToggleButton();
-		showTabSeparatorsCheckBox = new JCheckBox();
 		tabsPopupPolicyLabel = new JLabel();
 		tabsPopupPolicyToolBar = new JToolBar();
 		popupAsNeededButton = new JToggleButton();
 		popupNeverButton = new JToggleButton();
+		showTabSeparatorsCheckBox = new JCheckBox();
+		scrollButtonsPlacementLabel = new JLabel();
+		scrollButtonsPlacementToolBar = new JToolBar();
+		scrollBothButton = new JToggleButton();
+		scrollTrailingButton = new JToggleButton();
 		tabTypeLabel = new JLabel();
 		tabTypeToolBar = new JToolBar();
 		underlinedTabTypeButton = new JToggleButton();
 		cardTabTypeButton = new JToggleButton();
+		tabRotationLabel = new JLabel();
+		tabRotationToolBar = new JToolBar();
+		rotationNoneButton = new JToggleButton();
+		rotationAutoButton = new JToggleButton();
+		rotationLeftButton = new JToggleButton();
+		rotationRightButton = new JToggleButton();
 
 		//======== this ========
 		setLayout(new MigLayout(
+			"insets 0,hidemode 3",
+			// columns
+			"[grow,fill]",
+			// rows
+			"[grow,fill]0" +
+			"[]0" +
+			"[]"));
+
+		//======== tabsScrollPane ========
+		{
+			tabsScrollPane.setBorder(BorderFactory.createEmptyBorder());
+
+			//======== panel6 ========
+			{
+				panel6.setLayout(new MigLayout(
 					"insets dialog,hidemode 3",
 					// columns
 					"[grow,fill]para" +
 					"[fill]para" +
 					"[fill]",
 					// rows
-			"[grow,fill]para" +
-			"[]" +
-			"[]"));
+					"[grow,fill]"));
 
 				//======== panel1 ========
 				{
@@ -589,7 +618,7 @@ class TabsPanel
 					panel1.add(tabAreaComponentsToolBar, "cell 0 7,alignx right,growx 0");
 					panel1.add(customComponentsTabbedPane, "cell 0 8");
 				}
-		add(panel1, "cell 0 0");
+				panel6.add(panel1, "cell 0 0");
 
 				//======== panel2 ========
 				{
@@ -641,7 +670,7 @@ class TabsPanel
 					panel2.add(alignTrailingTabbedPane, "cell 0 10");
 					panel2.add(alignFillTabbedPane, "cell 0 11");
 				}
-		add(panel2, "cell 1 0,growy");
+				panel6.add(panel2, "cell 1 0,growy");
 
 				//======== panel3 ========
 				{
@@ -698,6 +727,7 @@ class TabsPanel
 							"[]" +
 							"[]" +
 							"[]" +
+							"[]" +
 							"[]"));
 
 						//---- tabAlignmentNoteLabel ----
@@ -717,24 +747,29 @@ class TabsPanel
 						{
 							tabAlignVerticalTabbedPane.setTabPlacement(SwingConstants.LEFT);
 						}
-				panel5.add(tabAlignVerticalTabbedPane, "cell 1 1 1 3,growy");
+						panel5.add(tabAlignVerticalTabbedPane, "cell 1 1 1 4,growy");
 						panel5.add(tabAlignCenterTabbedPane, "cell 0 2");
 						panel5.add(tabAlignTrailingTabbedPane, "cell 0 3");
 					}
 					panel3.add(panel5, "cell 0 9");
 				}
-		add(panel3, "cell 2 0");
-		add(separator2, "cell 0 1 3 1");
+				panel6.add(panel3, "cell 2 0");
+			}
+			tabsScrollPane.setViewportView(panel6);
+		}
+		add(tabsScrollPane, "cell 0 0");
+		add(separator2, "cell 0 1");
 
 		//======== panel4 ========
 		{
 			panel4.setLayout(new MigLayout(
-				"insets 0,hidemode 3",
+				"insets panel,hidemode 3",
 				// columns
 				"[]" +
 				"[fill]para" +
 				"[fill]" +
 				"[fill]para" +
+				"[fill]" +
 				"[fill]",
 				// rows
 				"[]" +
@@ -770,38 +805,9 @@ class TabsPanel
 			}
 			panel4.add(scrollButtonsPolicyToolBar, "cell 1 0");
 
-			//---- scrollButtonsPlacementLabel ----
-			scrollButtonsPlacementLabel.setText("Scroll buttons placement:");
-			panel4.add(scrollButtonsPlacementLabel, "cell 2 0");
-
-			//======== scrollButtonsPlacementToolBar ========
-			{
-				scrollButtonsPlacementToolBar.setFloatable(false);
-				scrollButtonsPlacementToolBar.setBorder(BorderFactory.createEmptyBorder());
-
-				//---- scrollBothButton ----
-				scrollBothButton.setText("both");
-				scrollBothButton.setSelected(true);
-				scrollBothButton.putClientProperty("FlatLaf.styleClass", "small");
-				scrollBothButton.addActionListener(e -> scrollButtonsPlacementChanged());
-				scrollButtonsPlacementToolBar.add(scrollBothButton);
-
-				//---- scrollTrailingButton ----
-				scrollTrailingButton.setText("trailing");
-				scrollTrailingButton.putClientProperty("FlatLaf.styleClass", "small");
-				scrollTrailingButton.addActionListener(e -> scrollButtonsPlacementChanged());
-				scrollButtonsPlacementToolBar.add(scrollTrailingButton);
-			}
-			panel4.add(scrollButtonsPlacementToolBar, "cell 3 0");
-
-			//---- showTabSeparatorsCheckBox ----
-			showTabSeparatorsCheckBox.setText("Show tab separators");
-			showTabSeparatorsCheckBox.addActionListener(e -> showTabSeparatorsChanged());
-			panel4.add(showTabSeparatorsCheckBox, "cell 4 0");
-
 			//---- tabsPopupPolicyLabel ----
 			tabsPopupPolicyLabel.setText("Tabs popup policy:");
-			panel4.add(tabsPopupPolicyLabel, "cell 0 1");
+			panel4.add(tabsPopupPolicyLabel, "cell 2 0");
 
 			//======== tabsPopupPolicyToolBar ========
 			{
@@ -821,7 +827,36 @@ class TabsPanel
 				popupNeverButton.addActionListener(e -> tabsPopupPolicyChanged());
 				tabsPopupPolicyToolBar.add(popupNeverButton);
 			}
-			panel4.add(tabsPopupPolicyToolBar, "cell 1 1");
+			panel4.add(tabsPopupPolicyToolBar, "cell 3 0");
+
+			//---- showTabSeparatorsCheckBox ----
+			showTabSeparatorsCheckBox.setText("Show tab separators");
+			showTabSeparatorsCheckBox.addActionListener(e -> showTabSeparatorsChanged());
+			panel4.add(showTabSeparatorsCheckBox, "cell 4 0 2 1,alignx left,growx 0");
+
+			//---- scrollButtonsPlacementLabel ----
+			scrollButtonsPlacementLabel.setText("Scroll buttons placement:");
+			panel4.add(scrollButtonsPlacementLabel, "cell 0 1");
+
+			//======== scrollButtonsPlacementToolBar ========
+			{
+				scrollButtonsPlacementToolBar.setFloatable(false);
+				scrollButtonsPlacementToolBar.setBorder(BorderFactory.createEmptyBorder());
+
+				//---- scrollBothButton ----
+				scrollBothButton.setText("both");
+				scrollBothButton.setSelected(true);
+				scrollBothButton.putClientProperty("FlatLaf.styleClass", "small");
+				scrollBothButton.addActionListener(e -> scrollButtonsPlacementChanged());
+				scrollButtonsPlacementToolBar.add(scrollBothButton);
+
+				//---- scrollTrailingButton ----
+				scrollTrailingButton.setText("trailing");
+				scrollTrailingButton.putClientProperty("FlatLaf.styleClass", "small");
+				scrollTrailingButton.addActionListener(e -> scrollButtonsPlacementChanged());
+				scrollButtonsPlacementToolBar.add(scrollTrailingButton);
+			}
+			panel4.add(scrollButtonsPlacementToolBar, "cell 1 1");
 
 			//---- tabTypeLabel ----
 			tabTypeLabel.setText("Tab type:");
@@ -845,8 +880,44 @@ class TabsPanel
 				tabTypeToolBar.add(cardTabTypeButton);
 			}
 			panel4.add(tabTypeToolBar, "cell 3 1");
+
+			//---- tabRotationLabel ----
+			tabRotationLabel.setText("Tab rotation:");
+			panel4.add(tabRotationLabel, "cell 4 1");
+
+			//======== tabRotationToolBar ========
+			{
+				tabRotationToolBar.setFloatable(false);
+				tabRotationToolBar.setBorder(BorderFactory.createEmptyBorder());
+
+				//---- rotationNoneButton ----
+				rotationNoneButton.setText("none");
+				rotationNoneButton.setSelected(true);
+				rotationNoneButton.putClientProperty("FlatLaf.styleClass", "small");
+				rotationNoneButton.addActionListener(e -> tabRotationChanged());
+				tabRotationToolBar.add(rotationNoneButton);
+
+				//---- rotationAutoButton ----
+				rotationAutoButton.setText("auto");
+				rotationAutoButton.putClientProperty("FlatLaf.styleClass", "small");
+				rotationAutoButton.addActionListener(e -> tabRotationChanged());
+				tabRotationToolBar.add(rotationAutoButton);
+
+				//---- rotationLeftButton ----
+				rotationLeftButton.setText("left");
+				rotationLeftButton.putClientProperty("FlatLaf.styleClass", "small");
+				rotationLeftButton.addActionListener(e -> tabRotationChanged());
+				tabRotationToolBar.add(rotationLeftButton);
+
+				//---- rotationRightButton ----
+				rotationRightButton.setText("right");
+				rotationRightButton.putClientProperty("FlatLaf.styleClass", "small");
+				rotationRightButton.addActionListener(e -> tabRotationChanged());
+				tabRotationToolBar.add(rotationRightButton);
 			}
-		add(panel4, "cell 0 2 3 1");
+			panel4.add(tabRotationToolBar, "cell 5 1");
+		}
+		add(panel4, "cell 0 2");
 
 		//---- tabPlacementButtonGroup ----
 		ButtonGroup tabPlacementButtonGroup = new ButtonGroup();
@@ -872,20 +943,27 @@ class TabsPanel
 		scrollButtonsPolicyButtonGroup.add(scrollAsNeededButton);
 		scrollButtonsPolicyButtonGroup.add(scrollNeverButton);
 
-		//---- scrollButtonsPlacementButtonGroup ----
-		ButtonGroup scrollButtonsPlacementButtonGroup = new ButtonGroup();
-		scrollButtonsPlacementButtonGroup.add(scrollBothButton);
-		scrollButtonsPlacementButtonGroup.add(scrollTrailingButton);
-
 		//---- tabsPopupPolicyButtonGroup ----
 		ButtonGroup tabsPopupPolicyButtonGroup = new ButtonGroup();
 		tabsPopupPolicyButtonGroup.add(popupAsNeededButton);
 		tabsPopupPolicyButtonGroup.add(popupNeverButton);
 
+		//---- scrollButtonsPlacementButtonGroup ----
+		ButtonGroup scrollButtonsPlacementButtonGroup = new ButtonGroup();
+		scrollButtonsPlacementButtonGroup.add(scrollBothButton);
+		scrollButtonsPlacementButtonGroup.add(scrollTrailingButton);
+
 		//---- tabTypeButtonGroup ----
 		ButtonGroup tabTypeButtonGroup = new ButtonGroup();
 		tabTypeButtonGroup.add(underlinedTabTypeButton);
 		tabTypeButtonGroup.add(cardTabTypeButton);
+
+		//---- tabRotationButtonGroup ----
+		ButtonGroup tabRotationButtonGroup = new ButtonGroup();
+		tabRotationButtonGroup.add(rotationNoneButton);
+		tabRotationButtonGroup.add(rotationAutoButton);
+		tabRotationButtonGroup.add(rotationLeftButton);
+		tabRotationButtonGroup.add(rotationRightButton);
 		// JFormDesigner - End of component initialization  //GEN-END:initComponents
 
 		if( FlatLafDemo.screenshotsMode ) {
@@ -961,18 +1039,24 @@ class TabsPanel
 	private JToggleButton scrollAsNeededSingleButton;
 	private JToggleButton scrollAsNeededButton;
 	private JToggleButton scrollNeverButton;
-	private JLabel scrollButtonsPlacementLabel;
-	private JToolBar scrollButtonsPlacementToolBar;
-	private JToggleButton scrollBothButton;
-	private JToggleButton scrollTrailingButton;
-	private JCheckBox showTabSeparatorsCheckBox;
 	private JLabel tabsPopupPolicyLabel;
 	private JToolBar tabsPopupPolicyToolBar;
 	private JToggleButton popupAsNeededButton;
 	private JToggleButton popupNeverButton;
+	private JCheckBox showTabSeparatorsCheckBox;
+	private JLabel scrollButtonsPlacementLabel;
+	private JToolBar scrollButtonsPlacementToolBar;
+	private JToggleButton scrollBothButton;
+	private JToggleButton scrollTrailingButton;
 	private JLabel tabTypeLabel;
 	private JToolBar tabTypeToolBar;
 	private JToggleButton underlinedTabTypeButton;
 	private JToggleButton cardTabTypeButton;
+	private JLabel tabRotationLabel;
+	private JToolBar tabRotationToolBar;
+	private JToggleButton rotationNoneButton;
+	private JToggleButton rotationAutoButton;
+	private JToggleButton rotationLeftButton;
+	private JToggleButton rotationRightButton;
 	// JFormDesigner - End of variables declaration  //GEN-END:variables
 }

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/TabsPanel.jfd

@@ -1,14 +1,29 @@
-JFDML JFormDesigner: "7.0.5.0.404" Java: "17" encoding: "UTF-8"
+JFDML JFormDesigner: "8.2.0.0.331" Java: "21" encoding: "UTF-8"
 
 new FormModel {
 	contentType: "form/swing"
 	root: new FormRoot {
 		add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
-			"$layoutConstraints": "insets dialog,hidemode 3"
-			"$columnConstraints": "[grow,fill]para[fill]para[fill]"
-			"$rowConstraints": "[grow,fill]para[][]"
+			"$layoutConstraints": "insets 0,hidemode 3"
+			"$columnConstraints": "[grow,fill]"
+			"$rowConstraints": "[grow,fill]0[]0[]"
 		} ) {
 			name: "this"
+			add( new FormContainer( "javax.swing.JScrollPane", new FormLayoutManager( class javax.swing.JScrollPane ) ) {
+				name: "tabsScrollPane"
+				"border": new javax.swing.border.EmptyBorder( 0, 0, 0, 0 )
+				auxiliary() {
+					"JavaCodeGenerator.variableLocal": true
+				}
+				add( new FormContainer( "com.formdev.flatlaf.demo.ScrollablePanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
+					"$columnConstraints": "[grow,fill]para[fill]para[fill]"
+					"$rowConstraints": "[grow,fill]"
+					"$layoutConstraints": "insets dialog,hidemode 3"
+				} ) {
+					name: "panel6"
+					auxiliary() {
+						"JavaCodeGenerator.variableLocal": true
+					}
 					add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
 						"$layoutConstraints": "insets 0,hidemode 3"
 						"$columnConstraints": "[grow,fill]"
@@ -396,7 +411,7 @@ new FormModel {
 						} )
 						add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
 							"$columnConstraints": "[grow,fill]para[fill]"
-					"$rowConstraints": "[][][][]"
+							"$rowConstraints": "[][][][][]"
 							"$layoutConstraints": "insets 0,hidemode 3"
 						} ) {
 							name: "panel5"
@@ -431,7 +446,7 @@ new FormModel {
 								name: "tabAlignVerticalTabbedPane"
 								"tabPlacement": 2
 							}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-						"value": "cell 1 1 1 3,growy"
+								"value": "cell 1 1 1 4,growy"
 							} )
 							add( new FormContainer( "javax.swing.JTabbedPane", new FormLayoutManager( class javax.swing.JTabbedPane ) ) {
 								name: "tabAlignCenterTabbedPane"
@@ -449,14 +464,18 @@ new FormModel {
 					}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 						"value": "cell 2 0"
 					} )
+				} )
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 0 0"
+			} )
 			add( new FormComponent( "javax.swing.JSeparator" ) {
 				name: "separator2"
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-				"value": "cell 0 1 3 1"
+				"value": "cell 0 1"
 			} )
 			add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
-				"$layoutConstraints": "insets 0,hidemode 3"
-				"$columnConstraints": "[][fill]para[fill][fill]para[fill]"
+				"$layoutConstraints": "insets panel,hidemode 3"
+				"$columnConstraints": "[][fill]para[fill][fill]para[fill][fill]"
 				"$rowConstraints": "[][center]"
 			} ) {
 				name: "panel4"
@@ -498,49 +517,11 @@ new FormModel {
 				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 					"value": "cell 1 0"
 				} )
-				add( new FormComponent( "javax.swing.JLabel" ) {
-					name: "scrollButtonsPlacementLabel"
-					"text": "Scroll buttons placement:"
-				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-					"value": "cell 2 0"
-				} )
-				add( new FormContainer( "javax.swing.JToolBar", new FormLayoutManager( class javax.swing.JToolBar ) ) {
-					name: "scrollButtonsPlacementToolBar"
-					"floatable": false
-					"border": #EmptyBorder0
-					add( new FormComponent( "javax.swing.JToggleButton" ) {
-						name: "scrollBothButton"
-						"text": "both"
-						"selected": true
-						"$buttonGroup": new FormReference( "scrollButtonsPlacementButtonGroup" )
-						"$client.FlatLaf.styleClass": "small"
-						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "scrollButtonsPlacementChanged", false ) )
-					} )
-					add( new FormComponent( "javax.swing.JToggleButton" ) {
-						name: "scrollTrailingButton"
-						"text": "trailing"
-						"$buttonGroup": new FormReference( "scrollButtonsPlacementButtonGroup" )
-						"$client.FlatLaf.styleClass": "small"
-						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "scrollButtonsPlacementChanged", false ) )
-					} )
-				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-					"value": "cell 3 0"
-				} )
-				add( new FormComponent( "javax.swing.JCheckBox" ) {
-					name: "showTabSeparatorsCheckBox"
-					"text": "Show tab separators"
-					auxiliary() {
-						"JavaCodeGenerator.variableLocal": false
-					}
-					addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "showTabSeparatorsChanged", false ) )
-				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-					"value": "cell 4 0"
-				} )
 				add( new FormComponent( "javax.swing.JLabel" ) {
 					name: "tabsPopupPolicyLabel"
 					"text": "Tabs popup policy:"
 				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-					"value": "cell 0 1"
+					"value": "cell 2 0"
 				} )
 				add( new FormContainer( "javax.swing.JToolBar", new FormLayoutManager( class javax.swing.JToolBar ) ) {
 					name: "tabsPopupPolicyToolBar"
@@ -561,6 +542,44 @@ new FormModel {
 						"$client.FlatLaf.styleClass": "small"
 						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "tabsPopupPolicyChanged", false ) )
 					} )
+				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+					"value": "cell 3 0"
+				} )
+				add( new FormComponent( "javax.swing.JCheckBox" ) {
+					name: "showTabSeparatorsCheckBox"
+					"text": "Show tab separators"
+					auxiliary() {
+						"JavaCodeGenerator.variableLocal": false
+					}
+					addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "showTabSeparatorsChanged", false ) )
+				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+					"value": "cell 4 0 2 1,alignx left,growx 0"
+				} )
+				add( new FormComponent( "javax.swing.JLabel" ) {
+					name: "scrollButtonsPlacementLabel"
+					"text": "Scroll buttons placement:"
+				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+					"value": "cell 0 1"
+				} )
+				add( new FormContainer( "javax.swing.JToolBar", new FormLayoutManager( class javax.swing.JToolBar ) ) {
+					name: "scrollButtonsPlacementToolBar"
+					"floatable": false
+					"border": #EmptyBorder0
+					add( new FormComponent( "javax.swing.JToggleButton" ) {
+						name: "scrollBothButton"
+						"text": "both"
+						"selected": true
+						"$buttonGroup": new FormReference( "scrollButtonsPlacementButtonGroup" )
+						"$client.FlatLaf.styleClass": "small"
+						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "scrollButtonsPlacementChanged", false ) )
+					} )
+					add( new FormComponent( "javax.swing.JToggleButton" ) {
+						name: "scrollTrailingButton"
+						"text": "trailing"
+						"$buttonGroup": new FormReference( "scrollButtonsPlacementButtonGroup" )
+						"$client.FlatLaf.styleClass": "small"
+						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "scrollButtonsPlacementChanged", false ) )
+					} )
 				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 					"value": "cell 1 1"
 				} )
@@ -591,47 +610,94 @@ new FormModel {
 				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 					"value": "cell 3 1"
 				} )
+				add( new FormComponent( "javax.swing.JLabel" ) {
+					name: "tabRotationLabel"
+					"text": "Tab rotation:"
 				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-				"value": "cell 0 2 3 1"
+					"value": "cell 4 1"
+				} )
+				add( new FormContainer( "javax.swing.JToolBar", new FormLayoutManager( class javax.swing.JToolBar ) ) {
+					name: "tabRotationToolBar"
+					"floatable": false
+					"border": #EmptyBorder0
+					add( new FormComponent( "javax.swing.JToggleButton" ) {
+						name: "rotationNoneButton"
+						"text": "none"
+						"selected": true
+						"$client.FlatLaf.styleClass": "small"
+						"$buttonGroup": new FormReference( "tabRotationButtonGroup" )
+						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "tabRotationChanged", false ) )
+					} )
+					add( new FormComponent( "javax.swing.JToggleButton" ) {
+						name: "rotationAutoButton"
+						"text": "auto"
+						"$client.FlatLaf.styleClass": "small"
+						"$buttonGroup": new FormReference( "tabRotationButtonGroup" )
+						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "tabRotationChanged", false ) )
+					} )
+					add( new FormComponent( "javax.swing.JToggleButton" ) {
+						name: "rotationLeftButton"
+						"text": "left"
+						"$client.FlatLaf.styleClass": "small"
+						"$buttonGroup": new FormReference( "tabRotationButtonGroup" )
+						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "tabRotationChanged", false ) )
+					} )
+					add( new FormComponent( "javax.swing.JToggleButton" ) {
+						name: "rotationRightButton"
+						"text": "right"
+						"$client.FlatLaf.styleClass": "small"
+						"$buttonGroup": new FormReference( "tabRotationButtonGroup" )
+						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "tabRotationChanged", false ) )
+					} )
+				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+					"value": "cell 5 1"
+				} )
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 0 2"
 			} )
 		}, new FormLayoutConstraints( null ) {
 			"location": new java.awt.Point( 0, 0 )
-			"size": new java.awt.Dimension( 1145, 895 )
+			"size": new java.awt.Dimension( 1145, 1045 )
 		} )
 		add( new FormNonVisual( "javax.swing.ButtonGroup" ) {
 			name: "tabPlacementButtonGroup"
 		}, new FormLayoutConstraints( null ) {
-			"location": new java.awt.Point( 5, 915 )
+			"location": new java.awt.Point( 5, 1080 )
 		} )
 		add( new FormNonVisual( "javax.swing.ButtonGroup" ) {
 			name: "closableTabsButtonGroup"
 		}, new FormLayoutConstraints( null ) {
-			"location": new java.awt.Point( 5, 970 )
+			"location": new java.awt.Point( 5, 1135 )
 		} )
 		add( new FormNonVisual( "javax.swing.ButtonGroup" ) {
 			name: "tabLayoutButtonGroup"
 		}, new FormLayoutConstraints( null ) {
-			"location": new java.awt.Point( 5, 1020 )
+			"location": new java.awt.Point( 5, 1185 )
 		} )
 		add( new FormNonVisual( "javax.swing.ButtonGroup" ) {
 			name: "tabsPopupPolicyButtonGroup"
 		}, new FormLayoutConstraints( null ) {
-			"location": new java.awt.Point( 200, 915 )
+			"location": new java.awt.Point( 200, 1080 )
 		} )
 		add( new FormNonVisual( "javax.swing.ButtonGroup" ) {
 			name: "scrollButtonsPolicyButtonGroup"
 		}, new FormLayoutConstraints( null ) {
-			"location": new java.awt.Point( 200, 965 )
+			"location": new java.awt.Point( 200, 1130 )
 		} )
 		add( new FormNonVisual( "javax.swing.ButtonGroup" ) {
 			name: "scrollButtonsPlacementButtonGroup"
 		}, new FormLayoutConstraints( null ) {
-			"location": new java.awt.Point( 200, 1020 )
+			"location": new java.awt.Point( 200, 1185 )
 		} )
 		add( new FormNonVisual( "javax.swing.ButtonGroup" ) {
 			name: "tabTypeButtonGroup"
 		}, new FormLayoutConstraints( null ) {
-			"location": new java.awt.Point( 0, 1072 )
+			"location": new java.awt.Point( 0, 1235 )
+		} )
+		add( new FormNonVisual( "javax.swing.ButtonGroup" ) {
+			name: "tabRotationButtonGroup"
+		}, new FormLayoutConstraints( null ) {
+			"location": new java.awt.Point( 200, 1235 )
 		} )
 	}
 }

flatlaf-demo/src/main/resources/com/formdev/flatlaf/demo/icons/collapse.svg

@@ -0,0 +1,4 @@
+<!-- Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license. -->
+<svg width="16" height="16" viewBox="0 0 16 16" fill="none" xmlns="http://www.w3.org/2000/svg">
+<path d="M1.5 14.5L6 10M14.5 1.5L9.99998 6.00001M2.5 9.50001H6.5L6.5 13.5M13.5 6.5L9.5 6.50003V2.5" stroke="#6E6E6E" stroke-linecap="round" stroke-linejoin="round"/>
+</svg>

flatlaf-demo/src/main/resources/com/formdev/flatlaf/demo/icons/expand.svg

@@ -0,0 +1,4 @@
+<!-- Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license. -->
+<svg width="16" height="16" viewBox="0 0 16 16" fill="none" xmlns="http://www.w3.org/2000/svg">
+<path d="M6.5 9.5L2 14M9.50003 6.50004L14 2.00001M5.5 14.5H1.5V10.5M10.5 1.5L14.5 1.50002V5.5" stroke="#6E6E6E" stroke-linecap="round" stroke-linejoin="round"/>
+</svg>

flatlaf-extras/README.md

@@ -33,7 +33,7 @@ build script:
     artifactId:  flatlaf-extras
     version:     (see button below)
 
-Otherwise download `flatlaf-extras-<version>.jar` here:
+Otherwise, download `flatlaf-extras-<version>.jar` here:
 
 [![Maven Central](https://maven-badges.herokuapp.com/maven-central/com.formdev/flatlaf-extras/badge.svg?style=flat-square&color=007ec6)](https://maven-badges.herokuapp.com/maven-central/com.formdev/flatlaf-extras)
 

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatAnimatedLafChange.java

@@ -133,8 +133,8 @@ public class FlatAnimatedLafChange
 	}
 
 	/**
-	 * Starts an animation that shows the snapshot (created by {@link #showSnapshot()}
-	 * with an decreasing alpha. At the end, the snapshot is removed and the new UI is shown.
+	 * Starts an animation that shows the snapshot (created by {@link #showSnapshot()})
+	 * with a decreasing alpha. At the end, the snapshot is removed and the new UI is shown.
 	 * Invoke after updating UI.
 	 */
 	public static void hideSnapshotWithAnimation() {

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatDesktop.java

@@ -119,7 +119,7 @@ public class FlatDesktop
 				(proxy, method, args) -> {
 					// Use invokeLater to release the listener firing for the case
 					// that the action listener shows a modal dialog.
-					// This (hopefully) prevents application hunging.
+					// This (hopefully) prevents application hanging.
 					EventQueue.invokeLater( () -> {
 						handler.run();
 					} );

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatSVGIcon.java

@@ -25,6 +25,7 @@ import java.awt.Image;
 import java.awt.Paint;
 import java.awt.Rectangle;
 import java.awt.RenderingHints;
+import java.awt.LinearGradientPaint;
 import java.awt.image.BufferedImage;
 import java.awt.image.RGBImageFilter;
 import java.io.File;
@@ -62,6 +63,8 @@ public class FlatSVGIcon
 	extends ImageIcon
 	implements DisabledIconProvider
 {
+	private static boolean loggingEnabled = true;
+	private static boolean svgCacheEnabled = true;
 	// cache that uses soft references for values, which allows freeing SVG documents if no longer used
 	private static final SoftCache<String, SVGDocument> svgCache = new SoftCache<>();
 	private static final SVGLoader svgLoader = new SVGLoader();
@@ -87,7 +90,7 @@ public class FlatSVGIcon
 	 * in the tag {@code <svg>} are used as icon size.
 	 * <p>
 	 * If using Java modules, the package containing the icon must be opened in {@code module-info.java}.
-	 * Otherwise use {@link #FlatSVGIcon(URL)}.
+	 * Otherwise, use {@link #FlatSVGIcon(URL)}.
 	 * <p>
 	 * This is cheap operation because the icon is only loaded when used.
 	 *
@@ -106,7 +109,7 @@ public class FlatSVGIcon
 	 * in the tag {@code <svg>} are used as icon size.
 	 * <p>
 	 * If using Java modules, the package containing the icon must be opened in {@code module-info.java}.
-	 * Otherwise use {@link #FlatSVGIcon(URL)}.
+	 * Otherwise, use {@link #FlatSVGIcon(URL)}.
 	 * <p>
 	 * This is cheap operation because the icon is only loaded when used.
 	 *
@@ -124,7 +127,7 @@ public class FlatSVGIcon
 	 * The icon is scaled if the given size is different to the size specified in the SVG file.
 	 * <p>
 	 * If using Java modules, the package containing the icon must be opened in {@code module-info.java}.
-	 * Otherwise use {@link #FlatSVGIcon(URL)}.
+	 * Otherwise, use {@link #FlatSVGIcon(URL)}.
 	 * <p>
 	 * This is cheap operation because the icon is only loaded when used.
 	 *
@@ -144,7 +147,7 @@ public class FlatSVGIcon
 	 * The icon is scaled if the given size is different to the size specified in the SVG file.
 	 * <p>
 	 * If using Java modules, the package containing the icon must be opened in {@code module-info.java}.
-	 * Otherwise use {@link #FlatSVGIcon(URL)}.
+	 * Otherwise, use {@link #FlatSVGIcon(URL)}.
 	 * <p>
 	 * This is cheap operation because the icon is only loaded when used.
 	 *
@@ -166,7 +169,7 @@ public class FlatSVGIcon
 	 * by the given scale factor.
 	 * <p>
 	 * If using Java modules, the package containing the icon must be opened in {@code module-info.java}.
-	 * Otherwise use {@link #FlatSVGIcon(URL)}.
+	 * Otherwise, use {@link #FlatSVGIcon(URL)}.
 	 * <p>
 	 * This is cheap operation because the icon is only loaded when used.
 	 *
@@ -187,7 +190,7 @@ public class FlatSVGIcon
 	 * by the given scale factor.
 	 * <p>
 	 * If using Java modules, the package containing the icon must be opened in {@code module-info.java}.
-	 * Otherwise use {@link #FlatSVGIcon(URL)}.
+	 * Otherwise, use {@link #FlatSVGIcon(URL)}.
 	 * <p>
 	 * This is cheap operation because the icon is only loaded when used.
 	 *
@@ -259,7 +262,7 @@ public class FlatSVGIcon
 	 * <p>
 	 * The input stream is loaded, parsed and closed immediately.
 	 *
-	 * @param in the input stream for reading a SVG resource
+	 * @param in the input stream for reading an SVG resource
 	 * @throws IOException if an I/O exception occurs
 	 * @since 2
 	 */
@@ -271,7 +274,8 @@ public class FlatSVGIcon
 
 			if( document == null ) {
 				loadFailed = true;
-				LoggingFacade.INSTANCE.logSevere( "FlatSVGIcon: failed to load SVG icon from input stream", null );
+				if( loggingEnabled )
+					LoggingFacade.INSTANCE.logConfig( "FlatSVGIcon: failed to load SVG icon from input stream", null );
 			}
 		}
 	}
@@ -449,8 +453,9 @@ public class FlatSVGIcon
 	 * @param colorFilter The color filter
 	 * @since 1.2
 	 */
-	public void setColorFilter( ColorFilter colorFilter ) {
+	public FlatSVGIcon setColorFilter( ColorFilter colorFilter ) {
 		this.colorFilter = colorFilter;
+		return this;
 	}
 
 	private void update() {
@@ -474,6 +479,7 @@ public class FlatSVGIcon
 
 			if( url == null ) {
 				loadFailed = true;
+				if( loggingEnabled )
 					LoggingFacade.INSTANCE.logConfig( "FlatSVGIcon: resource '" + name + "' not found (if using Java modules, check whether icon package is opened in module-info.java)", null );
 				return;
 			}
@@ -484,6 +490,9 @@ public class FlatSVGIcon
 	}
 
 	static synchronized SVGDocument loadSVG( URL url ) {
+		if( !svgCacheEnabled )
+			return loadSVGUncached( url );
+
 		// get from our cache
 		String cacheKey = url.toString();
 		SVGDocument document = svgCache.get( cacheKey );
@@ -491,18 +500,25 @@ public class FlatSVGIcon
 			return document;
 
 		// load SVG document
-		document = svgLoader.load( url );
-
-		if( document == null ) {
-			LoggingFacade.INSTANCE.logSevere( "FlatSVGIcon: failed to load '" + url + "'", null );
-			return null;
-		}
+		document = loadSVGUncached( url );
 
 		svgCache.put( cacheKey, document );
 
 		return document;
 	}
 
+	private static SVGDocument loadSVGUncached( URL url ) {
+		SVGDocument document = svgLoader.load( url );
+
+		if( document == null ) {
+			if( loggingEnabled )
+				LoggingFacade.INSTANCE.logConfig( "FlatSVGIcon: failed to load '" + url + "'", null );
+			return null;
+		}
+
+		return document;
+	}
+
 	private URL getIconURL( String name, boolean dark ) {
 		if( dark ) {
 			int dotIndex = name.lastIndexOf( '.' );
@@ -611,6 +627,9 @@ public class FlatSVGIcon
 	}
 
 	private void paintSvgError( Graphics2D g, int x, int y ) {
+		if( g instanceof GraphicsFilter )
+			((GraphicsFilter)g).setColorUnfiltered( Color.red );
+		else
 			g.setColor( Color.red );
 		g.fillRect( x, y, getIconWidth(), getIconHeight() );
 	}
@@ -692,6 +711,34 @@ public class FlatSVGIcon
 		darkLaf = FlatLaf.isLafDark();
 	}
 
+	/** @since 3.4.1 */
+	public static boolean isLoggingEnabled() {
+		return loggingEnabled;
+	}
+
+	/** @since 3.4.1 */
+	public static void setLoggingEnabled( boolean loggingEnabled ) {
+		FlatSVGIcon.loggingEnabled = loggingEnabled;
+	}
+
+	/** @since 3.4.1 */
+	public static boolean isSVGDocumentEnabled() {
+		return svgCacheEnabled;
+	}
+
+	/** @since 3.4.1 */
+	public static void setSVGDocumentEnabled( boolean svgCacheEnabled ) {
+		FlatSVGIcon.svgCacheEnabled = svgCacheEnabled;
+
+		if( !svgCacheEnabled )
+			clearSVGDocumentCache();
+	}
+
+	/** @since 3.4.1 */
+	public static void clearSVGDocumentCache() {
+		svgCache.clear();
+	}
+
 	//---- class ColorFilter --------------------------------------------------
 
 	/**
@@ -978,10 +1025,23 @@ public class FlatSVGIcon
 			super.setColor( filterColor( c ) );
 		}
 
+		void setColorUnfiltered( Color c ) {
+			super.setColor( c );
+		}
+
 		@Override
 		public void setPaint( Paint paint ) {
 			if( paint instanceof Color )
 				paint = filterColor( (Color) paint );
+			else if( paint instanceof LinearGradientPaint ) {
+				LinearGradientPaint oldPaint = (LinearGradientPaint) paint;
+				Color[] newColors = filterColors( oldPaint.getColors() );
+				if( newColors != null ) {
+					paint = new LinearGradientPaint( oldPaint.getStartPoint(), oldPaint.getEndPoint(),
+						oldPaint.getFractions(), newColors, oldPaint.getCycleMethod(),
+						oldPaint.getColorSpace(), oldPaint.getTransform() );
+				}
+			}
 			super.setPaint( paint );
 		}
 
@@ -1001,5 +1061,15 @@ public class FlatSVGIcon
 			}
 			return color;
 		}
+
+		private Color[] filterColors( Color[] colors ) {
+			Color[] newColors = new Color[colors.length];
+			boolean changed = false;
+			for( int i = 0; i < colors.length; i++ ) {
+				newColors[i] = filterColor( colors[i] );
+				changed = (changed || newColors[i] != colors[i]);
+			}
+			return changed ? newColors : null;
+		}
 	}
 }

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatSVGUtils.java

@@ -46,10 +46,10 @@ public class FlatSVGUtils
 	 * then a single multi-resolution image is returned that creates images on demand
 	 * for requested sizes from SVG.
 	 * This has the advantage that only images for used sizes are created.
-	 * Also if unusual sizes are requested (e.g. 18x18), then they are created from SVG.
+	 * Also, if unusual sizes are requested (e.g. 18x18), then they are created from SVG.
 	 * <p>
 	 * If using Java modules, the package containing the SVG must be opened in {@code module-info.java}.
-	 * Otherwise use {@link #createWindowIconImages(URL)}.
+	 * Otherwise, use {@link #createWindowIconImages(URL)}.
 	 *
 	 * @param svgName the name of the SVG resource (a '/'-separated path)
 	 * @return list of icon images with different sizes (16x16, 20x20, 24x24, 28x28, 32x32, 48x48 and 64x64)
@@ -69,7 +69,7 @@ public class FlatSVGUtils
 	 * then a single multi-resolution image is returned that creates images on demand
 	 * for requested sizes from SVG.
 	 * This has the advantage that only images for used sizes are created.
-	 * Also if unusual sizes are requested (e.g. 18x18), then they are created from SVG.
+	 * Also, if unusual sizes are requested (e.g. 18x18), then they are created from SVG.
 	 * <p>
 	 * This method is useful if using Java modules and the package containing the SVG
 	 * is not opened in {@code module-info.java}.
@@ -92,7 +92,7 @@ public class FlatSVGUtils
 					// any size is created on demand when
 					// MultiResolutionImage.getResolutionVariant(double destImageWidth, double destImageHeight)
 					// is invoked.
-					// This sizes are only used by MultiResolutionImage.getResolutionVariants().
+					// These sizes are only used by MultiResolutionImage.getResolutionVariants().
 					new Dimension( 16, 16 ),	// 100%
 					new Dimension( 20, 20 ),	// 125%
 					new Dimension( 24, 24 ),	// 150%
@@ -120,7 +120,7 @@ public class FlatSVGUtils
 	 * Creates a buffered image and renders the given SVG into it.
 	 * <p>
 	 * If using Java modules, the package containing the SVG must be opened in {@code module-info.java}.
-	 * Otherwise use {@link #svg2image(URL, int, int)}.
+	 * Otherwise, use {@link #svg2image(URL, int, int)}.
 	 *
 	 * @param svgName the name of the SVG resource (a '/'-separated path)
 	 * @param width the width of the image
@@ -154,7 +154,7 @@ public class FlatSVGUtils
 	 * Creates a buffered image and renders the given SVG into it.
 	 * <p>
 	 * If using Java modules, the package containing the SVG must be opened in {@code module-info.java}.
-	 * Otherwise use {@link #svg2image(URL, float)}.
+	 * Otherwise, use {@link #svg2image(URL, float)}.
 	 *
 	 * @param svgName the name of the SVG resource (a '/'-separated path)
 	 * @param scaleFactor the amount by which the SVG size is scaled

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatUIDefaultsInspector.java

@@ -557,7 +557,7 @@ public class FlatUIDefaultsInspector
 		// JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
 		panel = new JPanel();
 		filterPanel = new JPanel();
-		flterLabel = new JLabel();
+		filterLabel = new JLabel();
 		filterField = new FlatTextField();
 		valueTypeLabel = new JLabel();
 		valueTypeField = new JComboBox<>();
@@ -580,11 +580,11 @@ public class FlatUIDefaultsInspector
 				((GridBagLayout)filterPanel.getLayout()).columnWeights = new double[] {0.0, 1.0, 0.0, 0.0, 1.0E-4};
 				((GridBagLayout)filterPanel.getLayout()).rowWeights = new double[] {0.0, 1.0E-4};
 
-				//---- flterLabel ----
-				flterLabel.setText("Filter:");
-				flterLabel.setLabelFor(filterField);
-				flterLabel.setDisplayedMnemonic('F');
-				filterPanel.add(flterLabel, new GridBagConstraints(0, 0, 1, 1, 0.0, 0.0,
+				//---- filterLabel ----
+				filterLabel.setText("Filter:");
+				filterLabel.setLabelFor(filterField);
+				filterLabel.setDisplayedMnemonic('F');
+				filterPanel.add(filterLabel, new GridBagConstraints(0, 0, 1, 1, 0.0, 0.0,
 					GridBagConstraints.CENTER, GridBagConstraints.BOTH,
 					new Insets(0, 0, 0, 10), 0, 0));
 
@@ -668,7 +668,7 @@ public class FlatUIDefaultsInspector
 	// JFormDesigner - Variables declaration - DO NOT MODIFY  //GEN-BEGIN:variables
 	private JPanel panel;
 	private JPanel filterPanel;
-	private JLabel flterLabel;
+	private JLabel filterLabel;
 	private FlatTextField filterField;
 	private JLabel valueTypeLabel;
 	private JComboBox<String> valueTypeField;

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatUIDefaultsInspector.jfd

@@ -15,7 +15,7 @@ new FormModel {
 			} ) {
 				name: "filterPanel"
 				add( new FormComponent( "javax.swing.JLabel" ) {
-					name: "flterLabel"
+					name: "filterLabel"
 					"text": "Filter:"
 					"labelFor": new FormReference( "filterField" )
 					"displayedMnemonic": 70

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/components/FlatButton.java

@@ -33,14 +33,14 @@ public class FlatButton
 	public enum ButtonType { none, square, roundRect, tab, help, toolBarButton, borderless }
 
 	/**
-	 * Returns type of a button.
+	 * Returns type of button.
 	 */
 	public ButtonType getButtonType() {
 		return getClientPropertyEnumString( BUTTON_TYPE, ButtonType.class, null, ButtonType.none );
 	}
 
 	/**
-	 * Specifies type of a button.
+	 * Specifies type of button.
 	 */
 	public void setButtonType( ButtonType buttonType ) {
 		if( buttonType == ButtonType.none )

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/components/FlatFormattedTextField.java

@@ -106,7 +106,7 @@ public class FlatFormattedTextField
 	 * The component should be not opaque because the text field border is painted
 	 * slightly inside the usually visible border in some cases.
 	 * E.g. when focused (in some themes) or when an outline color is specified
-	 * (see {@link #setOutline(Object)}.
+	 * (see {@link #setOutline(Object)}).
 	 *
 	 * @since 2
 	 */
@@ -135,7 +135,7 @@ public class FlatFormattedTextField
 	 * The component should be not opaque because the text field border is painted
 	 * slightly inside the usually visible border in some cases.
 	 * E.g. when focused (in some themes) or when an outline color is specified
-	 * (see {@link #setOutline(Object)}.
+	 * (see {@link #setOutline(Object)}).
 	 *
 	 * @since 2
 	 */

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/components/FlatPasswordField.java

@@ -106,7 +106,7 @@ public class FlatPasswordField
 	 * The component should be not opaque because the text field border is painted
 	 * slightly inside the usually visible border in some cases.
 	 * E.g. when focused (in some themes) or when an outline color is specified
-	 * (see {@link #setOutline(Object)}.
+	 * (see {@link #setOutline(Object)}).
 	 *
 	 * @since 2
 	 */
@@ -135,7 +135,7 @@ public class FlatPasswordField
 	 * The component should be not opaque because the text field border is painted
 	 * slightly inside the usually visible border in some cases.
 	 * E.g. when focused (in some themes) or when an outline color is specified
-	 * (see {@link #setOutline(Object)}.
+	 * (see {@link #setOutline(Object)}).
 	 *
 	 * @since 2
 	 */

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/components/FlatSplitPane.java

@@ -16,6 +16,7 @@
 
 package com.formdev.flatlaf.extras.components;
 
+import static com.formdev.flatlaf.FlatClientProperties.*;
 import javax.swing.JSplitPane;
 
 /**
@@ -26,6 +27,29 @@ import javax.swing.JSplitPane;
  */
 public class FlatSplitPane
 	extends JSplitPane
-	implements FlatStyleableComponent
+	implements FlatComponentExtension, FlatStyleableComponent
 {
+	// NOTE: enum names must be equal to allowed strings
+	/** @since 3.4.1 */ public enum ExpandableSide { both, left, right }
+
+	/**
+	 * Returns what side of the spilt pane is allowed to expand
+	 * via one-touch expanding arrow buttons.
+	 *
+	 * @since 3.4.1
+	 */
+	public ExpandableSide getExpandableSide() {
+		return getClientPropertyEnumString( SPLIT_PANE_EXPANDABLE_SIDE, ExpandableSide.class,
+			null, ExpandableSide.both );
+	}
+
+	/**
+	 * Specifies what side of the spilt pane is allowed to expand
+	 * via one-touch expanding arrow buttons.
+	 *
+	 * @since 3.4.1
+	 */
+	public void setExpandableSide( ExpandableSide expandableSide ) {
+		putClientPropertyEnumString( SPLIT_PANE_EXPANDABLE_SIDE, expandableSide );
+	}
 }

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/components/FlatTabbedPane.java

@@ -502,6 +502,29 @@ public class FlatTabbedPane
 	}
 
 
+	// NOTE: enum names must be equal to allowed strings
+	/** @since 3.3 */ public enum TabRotation { none, auto, left, right }
+
+	/**
+	 * Returns how the tabs should be rotated.
+	 *
+	 * @since 3.3
+	 */
+	public TabRotation getTabRotation() {
+		return getClientPropertyEnumString( TABBED_PANE_TAB_ROTATION, TabRotation.class,
+			"TabbedPane.tabRotation", TabRotation.none );
+	}
+
+	/**
+	 * Specifies how the tabs should be rotated.
+	 *
+	 * @since 3.3
+	 */
+	public void setTabRotation( TabRotation tabRotation ) {
+		putClientPropertyEnumString( TABBED_PANE_TAB_ROTATION, tabRotation );
+	}
+
+
 	/**
 	 * Returns the tab icon placement (relative to tab title).
 	 */

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/components/FlatTextField.java

@@ -105,7 +105,7 @@ public class FlatTextField
 	 * The component should be not opaque because the text field border is painted
 	 * slightly inside the usually visible border in some cases.
 	 * E.g. when focused (in some themes) or when an outline color is specified
-	 * (see {@link #setOutline(Object)}.
+	 * (see {@link #setOutline(Object)}).
 	 *
 	 * @since 2
 	 */
@@ -134,7 +134,7 @@ public class FlatTextField
 	 * The component should be not opaque because the text field border is painted
 	 * slightly inside the usually visible border in some cases.
 	 * E.g. when focused (in some themes) or when an outline color is specified
-	 * (see {@link #setOutline(Object)}.
+	 * (see {@link #setOutline(Object)}).
 	 *
 	 * @since 2
 	 */