Merge branch 'windows-full-window-content'

CHANGELOG.md

@@ -5,6 +5,9 @@ FlatLaf Change Log
 
 #### 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)

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

@@ -257,13 +257,36 @@ 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
 	 */
@@ -274,7 +297,7 @@ public interface FlatClientProperties
 
 	/**
 	 * Marks the panel as placeholder for the iconfify/maximize/close buttons
-	 * in fullWindowContent mode.
+	 * 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}.
@@ -462,6 +485,32 @@ 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.

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

@@ -21,11 +21,12 @@ 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;
@@ -218,13 +219,13 @@ 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( !isSupported() )
 			return;
 
-		nativeProvider.updateTitleBarInfo( window, titleBarHeight, hitTestSpots,
+		nativeProvider.updateTitleBarInfo( window, titleBarHeight, captionHitTestCallback,
 			appIconBounds, minimizeButtonBounds, maximizeButtonBounds, closeButtonBounds );
 	}
 
@@ -270,7 +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 );
 

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

@@ -269,15 +269,28 @@ 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;
+
+	// 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( newTitlePane != null )
+		if( newTitlePane != null ) {
-			layeredPane.add( newTitlePane, TITLE_PANE_LAYER );
+			layeredPane.add( newTitlePane, getLayerForTitlePane() );
+			layeredPane.add( newTitlePane.mouseLayer, TITLE_PANE_MOUSE_LAYER );
+		}
 
 		titlePane = newTitlePane;
 	}
@@ -430,6 +443,17 @@ public class FlatRootPaneUI
 					titlePane.titleBarColorsChanged();
 				break;
 
+			case FlatClientProperties.FULL_WINDOW_CONTENT:
+				if( titlePane != null ) {
+					rootPane.getLayeredPane().setLayer( titlePane, getLayerForTitlePane() );
+					titlePane.updateIcon();
+					titlePane.updateVisibility();
+					titlePane.updateFullWindowContentButtonsBoundsProperty();
+				}
+				FullWindowContentSupport.revalidatePlaceholders( rootPane );
+				rootPane.revalidate();
+				break;
+
 			case FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_BOUNDS:
 				FullWindowContentSupport.revalidatePlaceholders( rootPane );
 				break;
@@ -471,11 +495,14 @@ public class FlatRootPaneUI
 		}
 	}
 
+	/** @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();
+		FlatTitlePane titlePane = getTitlePane( rootPane );
-		return ui instanceof FlatRootPaneUI &&
+		return titlePane != null && titlePane.isMenuBarEmbedded();
-			((FlatRootPaneUI)ui).titlePane != null &&
-			((FlatRootPaneUI)ui).titlePane.isMenuBarEmbedded();
 	}
 
 	/** @since 2.4 */
@@ -511,24 +538,22 @@ 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())
+				if( menuBar != null && menuBar.isVisible() ) {
-					? getSizeFunc.apply( menuBar )
+					Dimension menuBarSize = getSizeFunc.apply( menuBar );
-					: new Dimension();
-
 					width = Math.max( width, menuBarSize.width );
 					height += menuBarSize.height;
 				}
+			}
 
 			Insets insets = rootPane.getInsets();
 
@@ -552,11 +577,22 @@ 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( !isFullWindowContent )
 					nextY += prefHeight;
 			}
 
@@ -568,7 +604,7 @@ 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();
@@ -576,13 +612,23 @@ 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 ) );

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

@@ -84,7 +84,7 @@ 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;
@@ -227,6 +227,15 @@ public class FlatSplitPaneUI
 			((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

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

@@ -182,7 +182,7 @@ import com.formdev.flatlaf.util.UIScale;
  */
 public class FlatTabbedPaneUI
 	extends BasicTabbedPaneUI
-	implements StyleableUI
+	implements StyleableUI, FlatTitlePane.TitleBarCaptionHitTest
 {
 	// tab type
 	/** @since 2 */ protected static final int TAB_TYPE_UNDERLINED = 0;
@@ -2300,6 +2300,17 @@ debug*/
 		return (rects[last].y + rects[last].height) - rects[0].y;
 	}
 
+	//---- interface FlatTitlePane.TitleBarCaptionHitTest ----
+
+	/** @since 3.4 */
+	@Override
+	public Boolean isTitleBarCaptionAt( int x, int y ) {
+		if( tabForCoordinate( tabPane, x, y ) >= 0 )
+			return false;
+
+		return null; // check children
+	}
+
 	//---- class TabCloseButton -----------------------------------------------
 
 	private static class TabCloseButton

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 +109,7 @@ 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";
 
 	/** @since 2.5 */ protected final Font titleFont;
 	protected final Color activeBackground;
@@ -131,7 +131,6 @@ 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 +149,23 @@ 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;
+
 	public FlatTitlePane( JRootPane rootPane ) {
 		this.rootPane = rootPane;
 
@@ -178,7 +194,6 @@ 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 +202,10 @@ public class FlatTitlePane
 		addSubComponents();
 		activeChanged( true );
 
-		addMouseListener( handler );
+		mouseLayer = new JPanel();
-		addMouseMotionListener( handler );
+		mouseLayer.setOpaque( false );
-
+		mouseLayer.addMouseListener( handler );
-		// necessary for closing window with double-click on icon
+		mouseLayer.addMouseMotionListener( handler );
-		iconLabel.addMouseListener( handler );
 
 		applyComponentOrientation( rootPane.getComponentOrientation() );
 	}
@@ -234,6 +248,11 @@ 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 +266,7 @@ 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 +314,9 @@ public class FlatTitlePane
 							horizontalGlue.getWidth(), titleLabel.getHeight() );
 					}
 				}
+
+				// clear hit-test cache
+				lastCaptionHitTestTime = 0;
 			}
 		} );
 
@@ -338,6 +360,13 @@ 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 +446,9 @@ 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 +474,7 @@ 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 +499,13 @@ 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 +560,11 @@ 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 +576,9 @@ 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,
@@ -620,21 +666,45 @@ 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 );
+			g.drawLine( 0, y, getWidth(), y );
-		}
-		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 );
 		}
 
-	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;
 
@@ -645,6 +715,9 @@ 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)
@@ -866,11 +939,14 @@ 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() ) {
@@ -928,71 +1004,17 @@ public class FlatTitlePane
 			}
 		}
 
-		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;
@@ -1007,18 +1029,101 @@ public class FlatTitlePane
 			: null;
 	}
 
-	protected Rectangle getNativeHitTestSpot( JComponent c ) {
+	/**
-		Dimension size = c.getSize();
+	 * Returns whether there is a component at the given location, that processes
-		if( size.width <= 0 || size.height <= 0 )
+	 * mouse events. E.g. buttons, menus, etc.
-			return null;
+	 * <p>
-
+	 * Note:
-		Point location = SwingUtilities.convertPoint( c, 0, 0, window );
+	 * <ul>
-		Rectangle r = new Rectangle( location, size );
+	 *   <li>This method is invoked often when mouse is moved over title bar
-		return r;
+	 *       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;
@@ -1116,7 +1221,7 @@ 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 ) {
@@ -1125,7 +1230,7 @@ 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(),
@@ -1275,7 +1380,7 @@ 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() ) {
@@ -1302,7 +1407,7 @@ 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
@@ -1415,4 +1520,27 @@ 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/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;
@@ -453,6 +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/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;
@@ -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 int titleBarHeight; // measured from window top edge, which may be out-of-screen if maximized
-		private Rectangle[] hitTestSpots;
+		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
+				// return HTCLIENT if mouse is over any Swing component in title bar
-				// in another thread while processing the array
+				// that processes mouse events (e.g. buttons, menus, etc)
-				Rectangle[] hitTestSpots2 = hitTestSpots;
+				//   - Windows ignores mouse events in this area
-				for( Rectangle spot : hitTestSpots2 ) {
+				try {
-					if( spot.contains( sx, sy ) )
+					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, Point pt ) {
-		}
+			return (rect != null && rect.contains( pt ) );
-
-		private boolean contains( Rectangle rect, int x, int y ) {
-			return (rect != null && rect.contains( x, y ) );
 		}
 
 		/**

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

@@ -209,9 +209,11 @@ class FullWindowContentSupport
 		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, r.width - 1, r.height - 1 );
+		g.drawLine( r.x, r.y, x2, y2 );
-		g.drawLine( r.x, r.height - 1, r.width - 1, r.y );
+		g.drawLine( r.x, y2, x2, r.y );
 		FlatUIUtils.resetRenderingHints( g, oldRenderingHints );
 	}
 }

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

@@ -831,7 +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

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

@@ -73,6 +73,7 @@ class DemoFrame
 		initComponents();
 		updateFontMenuItems();
 		initAccentColors();
+		initFullWindowContent();
 		controlBar.initialize( this, tabbedPane );
 
 		setIconImages( FlatSVGUtils.createWindowIconImages( "/com/formdev/flatlaf/demo/FlatLaf.svg" ) );
@@ -101,9 +102,6 @@ class DemoFrame
 					rootPane.putClientProperty( "apple.awt.windowTitleVisible", false );
 				else
 					setTitle( null );
-
-				// uncomment this line to see title bar buttons placeholders in fullWindowContent mode
-//				UIManager.put( "FlatLaf.debug.panel.showPlaceholders", true );
 			}
 
 			// enable full screen mode for this window (for Java 8 - 10; not necessary for Java 11+)
@@ -463,9 +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();
@@ -528,8 +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 ========
@@ -538,7 +566,7 @@ class DemoFrame
 		Container contentPane = getContentPane();
 		contentPane.setLayout(new BorderLayout());
 
-		//======== menuBar1 ========
+		//======== menuBar ========
 		{
 
 			//======== fileMenu ========
@@ -583,7 +611,7 @@ class DemoFrame
 				exitMenuItem.addActionListener(e -> exitActionPerformed());
 				fileMenu.add(exitMenuItem);
 			}
-			menuBar1.add(fileMenu);
+			menuBar.add(fileMenu);
 
 			//======== editMenu ========
 			{
@@ -636,7 +664,7 @@ class DemoFrame
 				deleteMenuItem.addActionListener(e -> menuItemActionPerformed(e));
 				editMenu.add(deleteMenuItem);
 			}
-			menuBar1.add(editMenu);
+			menuBar.add(editMenu);
 
 			//======== viewMenu ========
 			{
@@ -736,7 +764,7 @@ class DemoFrame
 				radioButtonMenuItem3.addActionListener(e -> menuItemActionPerformed(e));
 				viewMenu.add(radioButtonMenuItem3);
 			}
-			menuBar1.add(viewMenu);
+			menuBar.add(viewMenu);
 
 			//======== fontMenu ========
 			{
@@ -760,7 +788,7 @@ class DemoFrame
 				decrFontMenuItem.addActionListener(e -> decrFont());
 				fontMenu.add(decrFontMenuItem);
 			}
-			menuBar1.add(fontMenu);
+			menuBar.add(fontMenu);
 
 			//======== optionsMenu ========
 			{
@@ -812,7 +840,7 @@ class DemoFrame
 				showUIDefaultsInspectorMenuItem.addActionListener(e -> showUIDefaultsInspector());
 				optionsMenu.add(showUIDefaultsInspectorMenuItem);
 			}
-			menuBar1.add(optionsMenu);
+			menuBar.add(optionsMenu);
 
 			//======== helpMenu ========
 			{
@@ -825,9 +853,9 @@ class DemoFrame
 				aboutMenuItem.addActionListener(e -> aboutActionPerformed());
 				helpMenu.add(aboutMenuItem);
 			}
-			menuBar1.add(helpMenu);
+			menuBar.add(helpMenu);
 		}
-		setJMenuBar(menuBar1);
+		setJMenuBar(menuBar);
 
 		//======== toolBarPanel ========
 		{
@@ -884,7 +912,7 @@ class DemoFrame
 			}
 			toolBarPanel.add(toolBar, BorderLayout.CENTER);
 		}
-		contentPane.add(toolBarPanel, BorderLayout.NORTH);
+		contentPane.add(toolBarPanel, BorderLayout.PAGE_START);
 
 		//======== contentPanel ========
 		{
@@ -904,13 +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(controlBar, BorderLayout.PAGE_END);
-		contentPane.add(themesPanel, BorderLayout.EAST);
+
+		//======== 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();
@@ -925,8 +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() );
+		menuBar.add( Box.createGlue() );
-		menuBar1.add( usersButton );
+		menuBar.add( usersButton );
 
 		cutMenuItem.addActionListener( new DefaultEditorKit.CutAction() );
 		copyMenuItem.addActionListener( new DefaultEditorKit.CopyAction() );
@@ -938,7 +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
@@ -959,9 +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() );
@@ -982,6 +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

@@ -74,7 +74,7 @@ new FormModel {
 					"value": "Center"
 				} )
 			}, new FormLayoutConstraints( class java.lang.String ) {
-				"value": "North"
+				"value": "First"
 			} )
 			add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
 				"$layoutConstraints": "insets dialog,hidemode 3"
@@ -115,7 +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"
 					} )
@@ -131,7 +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"
@@ -140,10 +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/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-jide-oss/src/main/java/com/formdev/flatlaf/jideoss/ui/FlatJideTabbedPaneUI.java

@@ -16,6 +16,7 @@
 
 package com.formdev.flatlaf.jideoss.ui;
 
+import static com.formdev.flatlaf.FlatClientProperties.COMPONENT_TITLE_BAR_CAPTION;
 import static com.formdev.flatlaf.FlatClientProperties.TABBED_PANE_HAS_FULL_BORDER;
 import static com.formdev.flatlaf.FlatClientProperties.TABBED_PANE_SHOW_TAB_SEPARATORS;
 import static com.formdev.flatlaf.FlatClientProperties.clientPropertyBoolean;
@@ -30,6 +31,7 @@ import java.awt.Graphics;
 import java.awt.Graphics2D;
 import java.awt.Insets;
 import java.awt.LayoutManager;
+import java.awt.Point;
 import java.awt.Rectangle;
 import java.awt.Shape;
 import java.awt.event.MouseListener;
@@ -37,6 +39,7 @@ import java.awt.event.MouseMotionListener;
 import java.awt.geom.Path2D;
 import java.awt.geom.Rectangle2D;
 import java.beans.PropertyChangeListener;
+import java.util.function.Function;
 import javax.swing.Icon;
 import javax.swing.JButton;
 import javax.swing.JComponent;
@@ -100,6 +103,25 @@ public class FlatJideTabbedPaneUI
 		return new FlatJideTabbedPaneUI();
 	}
 
+	@Override
+	public void installUI( JComponent c ) {
+		super.installUI( c );
+
+		c.putClientProperty( COMPONENT_TITLE_BAR_CAPTION,
+			(Function<Point, Boolean>) pt -> {
+				if( tabForCoordinate( _tabPane, pt.x, pt.y ) >= 0 )
+					return false;
+
+				return null; // check children
+			} );
+	}
+
+	@Override
+	public void uninstallUI( JComponent c ) {
+		super.uninstallUI( c );
+		c.putClientProperty( COMPONENT_TITLE_BAR_CAPTION, null );
+	}
+
 	@Override
 	protected void installDefaults() {
 		super.installDefaults();

flatlaf-natives/flatlaf-natives-jna/src/main/java/com/formdev/flatlaf/natives/jna/windows/FlatWindowsNativeWindowBorder.java

@@ -32,8 +32,8 @@ 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;
@@ -164,7 +164,7 @@ public 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 )
 	{
@@ -173,7 +173,7 @@ public 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 );
@@ -351,7 +351,7 @@ public class FlatWindowsNativeWindowBorder
 
 		// Swing coordinates/values may be scaled on a HiDPI screen
 		private int titleBarHeight;
-		private Rectangle[] hitTestSpots;
+		private Predicate<Point> captionHitTestCallback;
 		private Rectangle appIconBounds;
 		private Rectangle minimizeButtonBounds;
 		private Rectangle maximizeButtonBounds;
@@ -644,53 +644,65 @@ public class FlatWindowsNativeWindowBorder
 
 			// 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 new LRESULT( 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 new LRESULT( 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 new LRESULT( 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 new LRESULT( HTCLOSE );
 
 			int resizeBorderHeight = getResizeHandleHeight();
 			boolean isOnResizeBorder = (y < resizeBorderHeight) &&
 				(User32.INSTANCE.GetWindowLong( hwnd, GWL_STYLE ) & WS_THICKFRAME) != 0;
-			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 new LRESULT( HTTOP );
+
+			boolean isOnTitleBar = (pt.y < titleBarHeight);
 			if( isOnTitleBar ) {
-				// use a second reference to the array to avoid that it can be changed
+				// return HTCLIENT if mouse is over any Swing component in title bar
-				// in another thread while processing the array
+				// that processes mouse events (e.g. buttons, menus, etc)
-				Rectangle[] hitTestSpots2 = hitTestSpots;
+				//   - Windows ignores mouse events in this area
-				for( Rectangle spot : hitTestSpots2 ) {
+				try {
-					if( spot.contains( sx, sy ) )
+					if( captionHitTestCallback != null && !captionHitTestCallback.test( pt ) )
+						return new LRESULT( 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 new LRESULT( HTCAPTION );
+			}
+
+			// return HTCLIENT
+			//   - Windows ignores mouse events in this area
 			return new LRESULT( HTCLIENT );
 		}
-				return new LRESULT( isOnResizeBorder ? HTTOP : HTCAPTION );
-			}
 
-			return new LRESULT( isOnResizeBorder ? HTTOP : HTCLIENT );
+		private boolean contains( Rectangle rect, Point pt ) {
-		}
+			return (rect != null && rect.contains( pt ) );
-
-		private boolean contains( Rectangle rect, int x, int y ) {
-			return (rect != null && rect.contains( x, y ) );
 		}
 
 		/**

flatlaf-testing/dumps/uidefaults/FlatDarkLaf_1.8.0.txt

@@ -1266,7 +1266,6 @@ TitlePane.inactiveBackground   #303234  HSL 210   4  20    javax.swing.plaf.Colo
 TitlePane.inactiveForeground   #8c8c8c  HSL   0   0  55    javax.swing.plaf.ColorUIResource [UI]
 TitlePane.maximizeIcon         [lazy] 44,30    com.formdev.flatlaf.icons.FlatWindowMaximizeIcon [UI]
 TitlePane.menuBarEmbedded      true
-TitlePane.menuBarResizeHeight  4
 TitlePane.menuBarTitleGap      40
 TitlePane.menuBarTitleMinimumGap 12
 TitlePane.noIconLeftGap        8

flatlaf-testing/dumps/uidefaults/FlatLightLaf_1.8.0.txt

@@ -1271,7 +1271,6 @@ TitlePane.inactiveBackground   #ffffff  HSL   0   0 100    javax.swing.plaf.Colo
 TitlePane.inactiveForeground   #8c8c8c  HSL   0   0  55    javax.swing.plaf.ColorUIResource [UI]
 TitlePane.maximizeIcon         [lazy] 44,30    com.formdev.flatlaf.icons.FlatWindowMaximizeIcon [UI]
 TitlePane.menuBarEmbedded      true
-TitlePane.menuBarResizeHeight  4
 TitlePane.menuBarTitleGap      40
 TitlePane.menuBarTitleMinimumGap 12
 TitlePane.noIconLeftGap        8

flatlaf-testing/dumps/uidefaults/FlatMacDarkLaf_1.8.0.txt

@@ -1276,7 +1276,6 @@ TitlePane.inactiveBackground   #323232  HSL   0   0  20    javax.swing.plaf.Colo
 TitlePane.inactiveForeground   #9a9a9a  HSL   0   0  60    javax.swing.plaf.ColorUIResource [UI]
 TitlePane.maximizeIcon         [lazy] 44,30    com.formdev.flatlaf.icons.FlatWindowMaximizeIcon [UI]
 TitlePane.menuBarEmbedded      true
-TitlePane.menuBarResizeHeight  4
 TitlePane.menuBarTitleGap      40
 TitlePane.menuBarTitleMinimumGap 12
 TitlePane.noIconLeftGap        8

flatlaf-testing/dumps/uidefaults/FlatMacLightLaf_1.8.0.txt

@@ -1280,7 +1280,6 @@ TitlePane.inactiveBackground   #ececec  HSL   0   0  93    javax.swing.plaf.Colo
 TitlePane.inactiveForeground   #b6b6b6  HSL   0   0  71    javax.swing.plaf.ColorUIResource [UI]
 TitlePane.maximizeIcon         [lazy] 44,30    com.formdev.flatlaf.icons.FlatWindowMaximizeIcon [UI]
 TitlePane.menuBarEmbedded      true
-TitlePane.menuBarResizeHeight  4
 TitlePane.menuBarTitleGap      40
 TitlePane.menuBarTitleMinimumGap 12
 TitlePane.noIconLeftGap        8

flatlaf-testing/dumps/uidefaults/FlatTestLaf_1.8.0.txt

@@ -1307,7 +1307,6 @@ TitlePane.inactiveBackground   #008800  HSL 120 100  27    javax.swing.plaf.Colo
 TitlePane.inactiveForeground   #ffffff  HSL   0   0 100    javax.swing.plaf.ColorUIResource [UI]
 TitlePane.maximizeIcon         [lazy] 44,30    com.formdev.flatlaf.icons.FlatWindowMaximizeIcon [UI]
 TitlePane.menuBarEmbedded      true
-TitlePane.menuBarResizeHeight  4
 TitlePane.menuBarTitleGap      40
 TitlePane.menuBarTitleMinimumGap 12
 TitlePane.noIconLeftGap        8

flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatWindowDecorationsTest.java

@@ -41,6 +41,9 @@ import net.miginfocom.swing.*;
 public class FlatWindowDecorationsTest
 	extends FlatTestPanel
 {
+	// same as in FlatTitlePane
+	private static final String KEY_DEBUG_SHOW_RECTANGLES = "FlatLaf.debug.titlebar.showRectangles";
+
 	public static void main( String[] args ) {
 		SwingUtilities.invokeLater( () -> {
 			if( SystemInfo.isLinux ) {
@@ -51,7 +54,7 @@ public class FlatWindowDecorationsTest
 
 			FlatTestFrame frame = FlatTestFrame.create( args, "FlatWindowDecorationsTest" );
 			frame.applyComponentOrientationToFrame = true;
-			UIManager.put( "FlatLaf.debug.titlebar.showRectangles", true );
+			UIManager.put( KEY_DEBUG_SHOW_RECTANGLES, true );
 
 			Class<?> cls = FlatWindowDecorationsTest.class;
 			List<Image> images = Arrays.asList(
@@ -117,6 +120,14 @@ public class FlatWindowDecorationsTest
 			rootPane.addPropertyChangeListener( "windowDecorationStyle", e -> {
 				updateDecorationStyleRadioButtons( rootPane );
 			} );
+			rootPane.addPropertyChangeListener( FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_BOUNDS, e -> {
+				Rectangle bounds = (Rectangle) e.getNewValue();
+				if( bounds != null ) {
+					fullWindowContentButtonsBoundsField.setText( bounds.width + ", " + bounds.height
+						+ "   @ " + bounds.x + ", " + bounds.y );
+				} else
+					fullWindowContentButtonsBoundsField.setText( "null" );
+			} );
 		}
 	}
 
@@ -309,12 +320,21 @@ debug*/
 		JLabel caption = new JLabel( "Caption" );
 		caption.setBackground( Color.green );
 		caption.setOpaque( true );
-		caption.putClientProperty( FlatClientProperties.COMPONENT_TITLE_BAR_CAPTION, true );
 
 		menuBar.add( caption );
 		menuBar.revalidate();
 	}
 
+	private void addTextField() {
+		JTextField textField = new JTextField( "text", 10 );
+
+		JPanel panel = new JPanel( new GridBagLayout() );
+		panel.add( textField, new GridBagConstraints() );
+
+		menuBar.add( panel );
+		menuBar.revalidate();
+	}
+
 	private void removeMenu() {
 		int menuCount = menuBar.getMenuCount();
 		if( menuCount <= 0 )
@@ -515,13 +535,31 @@ debug*/
 			rootPane.putClientProperty( FlatClientProperties.TITLE_BAR_SHOW_CLOSE, showCloseCheckBox.isSelected() ? null : false );
 	}
 
+	private void fullWindowContentChanged() {
+		JRootPane rootPane = getWindowRootPane();
+		if( rootPane != null ) {
+			boolean selected = fullWindowContentCheckBox.isSelected();
+			rootPane.putClientProperty( FlatClientProperties.FULL_WINDOW_CONTENT, selected ? true : null );
+
+			showIconCheckBox.setEnabled( !selected );
+			showTitleCheckBox.setEnabled( !selected );
+		}
+	}
+
 	private JRootPane getWindowRootPane() {
 		Window window = SwingUtilities.windowForComponent( this );
-		if( window instanceof JFrame )
+		return (window instanceof RootPaneContainer)
-			return ((JFrame)window).getRootPane();
+			? ((RootPaneContainer)window).getRootPane()
-		else if( window instanceof JDialog )
+			: null;
-			return ((JDialog)window).getRootPane();
+	}
-		return null;
+
+	private void showRectangles() {
+		JRootPane rootPane = getWindowRootPane();
+		if( rootPane != null ) {
+			UIManager.put( KEY_DEBUG_SHOW_RECTANGLES, showRectanglesCheckBox.isSelected() );
+			rootPane.revalidate();
+			rootPane.repaint();
+		}
 	}
 
 	private void initComponents() {
@@ -538,6 +576,9 @@ debug*/
 		showIconifyCheckBox = new JCheckBox();
 		showMaximizeCheckBox = new JCheckBox();
 		showCloseCheckBox = new JCheckBox();
+		fullWindowContentCheckBox = new JCheckBox();
+		JLabel fullWindowContentButtonsBoundsLabel = new JLabel();
+		fullWindowContentButtonsBoundsField = new JLabel();
 		JPanel panel6 = new JPanel();
 		menuBarCheckBox = new JCheckBox();
 		menuBarEmbeddedCheckBox = new JCheckBox();
@@ -548,6 +589,7 @@ debug*/
 		addMenuButton = new JButton();
 		addGlueButton = new JButton();
 		addCaptionButton = new JButton();
+		addTextFieldButton = new JButton();
 		removeMenuButton = new JButton();
 		changeMenuButton = new JButton();
 		changeTitleButton = new JButton();
@@ -578,6 +620,7 @@ debug*/
 		typeNormalRadioButton = new JRadioButton();
 		typeUtilityRadioButton = new JRadioButton();
 		typeSmallRadioButton = new JRadioButton();
+		showRectanglesCheckBox = new JCheckBox();
 		menuBar = new JMenuBar();
 		JMenu fileMenu = new JMenu();
 		JMenuItem newMenuItem = new JMenuItem();
@@ -616,6 +659,7 @@ debug*/
 			// rows
 			"[fill]" +
 			"[fill]" +
+			"[]" +
 			"[]"));
 
 		//======== panel7 ========
@@ -673,6 +717,8 @@ debug*/
 				"[]" +
 				"[]" +
 				"[]" +
+				"[]rel" +
+				"[]rel" +
 				"[]"));
 
 			//---- showIconCheckBox ----
@@ -703,6 +749,19 @@ debug*/
 			showCloseCheckBox.setSelected(true);
 			showCloseCheckBox.addActionListener(e -> showCloseChanged());
 			panel4.add(showCloseCheckBox, "cell 0 4");
+
+			//---- fullWindowContentCheckBox ----
+			fullWindowContentCheckBox.setText("full window content");
+			fullWindowContentCheckBox.addActionListener(e -> fullWindowContentChanged());
+			panel4.add(fullWindowContentCheckBox, "cell 0 5");
+
+			//---- fullWindowContentButtonsBoundsLabel ----
+			fullWindowContentButtonsBoundsLabel.setText("Buttons bounds:");
+			panel4.add(fullWindowContentButtonsBoundsLabel, "cell 0 6");
+
+			//---- fullWindowContentButtonsBoundsField ----
+			fullWindowContentButtonsBoundsField.setText("null");
+			panel4.add(fullWindowContentButtonsBoundsField, "cell 0 6");
 		}
 		add(panel4, "cell 1 0");
 
@@ -761,6 +820,7 @@ debug*/
 				"[]" +
 				"[]" +
 				"[]" +
+				"[]" +
 				"[]unrel" +
 				"[]"));
 
@@ -779,20 +839,25 @@ debug*/
 			addCaptionButton.addActionListener(e -> addCaption());
 			panel3.add(addCaptionButton, "cell 0 2");
 
+			//---- addTextFieldButton ----
+			addTextFieldButton.setText("Add text field");
+			addTextFieldButton.addActionListener(e -> addTextField());
+			panel3.add(addTextFieldButton, "cell 0 3");
+
 			//---- removeMenuButton ----
 			removeMenuButton.setText("Remove menu");
 			removeMenuButton.addActionListener(e -> removeMenu());
-			panel3.add(removeMenuButton, "cell 0 3");
+			panel3.add(removeMenuButton, "cell 0 4");
 
 			//---- changeMenuButton ----
 			changeMenuButton.setText("Change menu");
 			changeMenuButton.addActionListener(e -> changeMenu());
-			panel3.add(changeMenuButton, "cell 0 4");
+			panel3.add(changeMenuButton, "cell 0 5");
 
 			//---- changeTitleButton ----
 			changeTitleButton.setText("Change title");
 			changeTitleButton.addActionListener(e -> changeTitle());
-			panel3.add(changeTitleButton, "cell 0 5");
+			panel3.add(changeTitleButton, "cell 0 6");
 		}
 		add(panel3, "cell 3 0 1 2,aligny top,growy 0");
 
@@ -969,6 +1034,12 @@ debug*/
 		typeSmallRadioButton.setText("Small");
 		add(typeSmallRadioButton, "cell 0 2 3 1");
 
+		//---- showRectanglesCheckBox ----
+		showRectanglesCheckBox.setText("Show debug title bar rectangles");
+		showRectanglesCheckBox.setSelected(true);
+		showRectanglesCheckBox.addActionListener(e -> showRectangles());
+		add(showRectanglesCheckBox, "cell 0 3");
+
 		//======== menuBar ========
 		{
 
@@ -1176,6 +1247,8 @@ debug*/
 	private JCheckBox showIconifyCheckBox;
 	private JCheckBox showMaximizeCheckBox;
 	private JCheckBox showCloseCheckBox;
+	private JCheckBox fullWindowContentCheckBox;
+	private JLabel fullWindowContentButtonsBoundsField;
 	private JCheckBox menuBarCheckBox;
 	private JCheckBox menuBarEmbeddedCheckBox;
 	private JCheckBox menuBarVisibleCheckBox;
@@ -1184,6 +1257,7 @@ debug*/
 	private JButton addMenuButton;
 	private JButton addGlueButton;
 	private JButton addCaptionButton;
+	private JButton addTextFieldButton;
 	private JButton removeMenuButton;
 	private JButton changeMenuButton;
 	private JButton changeTitleButton;
@@ -1209,6 +1283,7 @@ debug*/
 	private JRadioButton typeNormalRadioButton;
 	private JRadioButton typeUtilityRadioButton;
 	private JRadioButton typeSmallRadioButton;
+	private JCheckBox showRectanglesCheckBox;
 	private JMenuBar menuBar;
 	// JFormDesigner - End of variables declaration  //GEN-END:variables
 }

flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatWindowDecorationsTest.jfd

@@ -9,7 +9,7 @@ new FormModel {
 		add( new FormContainer( "com.formdev.flatlaf.testing.FlatTestPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
 			"$layoutConstraints": "ltr,insets dialog,hidemode 3"
 			"$columnConstraints": "[left][fill][fill][fill]"
-			"$rowConstraints": "[fill][fill][]"
+			"$rowConstraints": "[fill][fill][][]"
 		} ) {
 			name: "this"
 			add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
@@ -77,7 +77,7 @@ new FormModel {
 			add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
 				"$layoutConstraints": "ltr,hidemode 3,gap 0 0"
 				"$columnConstraints": "[grow,left]"
-				"$rowConstraints": "[][][][][]"
+				"$rowConstraints": "[][][][][]rel[]rel[]"
 			} ) {
 				name: "panel4"
 				"border": new javax.swing.border.TitledBorder( "Title Bar" )
@@ -135,6 +135,31 @@ new FormModel {
 				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 					"value": "cell 0 4"
 				} )
+				add( new FormComponent( "javax.swing.JCheckBox" ) {
+					name: "fullWindowContentCheckBox"
+					"text": "full window content"
+					auxiliary() {
+						"JavaCodeGenerator.variableLocal": false
+					}
+					addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "fullWindowContentChanged", false ) )
+				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+					"value": "cell 0 5"
+				} )
+				add( new FormComponent( "javax.swing.JLabel" ) {
+					name: "fullWindowContentButtonsBoundsLabel"
+					"text": "Buttons bounds:"
+				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+					"value": "cell 0 6"
+				} )
+				add( new FormComponent( "javax.swing.JLabel" ) {
+					name: "fullWindowContentButtonsBoundsField"
+					"text": "null"
+					auxiliary() {
+						"JavaCodeGenerator.variableLocal": false
+					}
+				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+					"value": "cell 0 6"
+				} )
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 				"value": "cell 1 0"
 			} )
@@ -204,7 +229,7 @@ new FormModel {
 			add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
 				"$layoutConstraints": "hidemode 3"
 				"$columnConstraints": "[fill]"
-				"$rowConstraints": "[][][][][]unrel[]"
+				"$rowConstraints": "[][][][][][]unrel[]"
 			} ) {
 				name: "panel3"
 				add( new FormComponent( "javax.swing.JButton" ) {
@@ -237,6 +262,16 @@ new FormModel {
 				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 					"value": "cell 0 2"
 				} )
+				add( new FormComponent( "javax.swing.JButton" ) {
+					name: "addTextFieldButton"
+					"text": "Add text field"
+					auxiliary() {
+						"JavaCodeGenerator.variableLocal": false
+					}
+					addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "addTextField", false ) )
+				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+					"value": "cell 0 3"
+				} )
 				add( new FormComponent( "javax.swing.JButton" ) {
 					name: "removeMenuButton"
 					"text": "Remove menu"
@@ -245,7 +280,7 @@ new FormModel {
 					}
 					addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "removeMenu", false ) )
 				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-					"value": "cell 0 3"
+					"value": "cell 0 4"
 				} )
 				add( new FormComponent( "javax.swing.JButton" ) {
 					name: "changeMenuButton"
@@ -255,7 +290,7 @@ new FormModel {
 					}
 					addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "changeMenu", false ) )
 				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-					"value": "cell 0 4"
+					"value": "cell 0 5"
 				} )
 				add( new FormComponent( "javax.swing.JButton" ) {
 					name: "changeTitleButton"
@@ -265,7 +300,7 @@ new FormModel {
 					}
 					addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "changeTitle", false ) )
 				}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-					"value": "cell 0 5"
+					"value": "cell 0 6"
 				} )
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 				"value": "cell 3 0 1 2,aligny top,growy 0"
@@ -552,6 +587,17 @@ new FormModel {
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 				"value": "cell 0 2 3 1"
 			} )
+			add( new FormComponent( "javax.swing.JCheckBox" ) {
+				name: "showRectanglesCheckBox"
+				"text": "Show debug title bar rectangles"
+				"selected": true
+				auxiliary() {
+					"JavaCodeGenerator.variableLocal": false
+				}
+				addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "showRectangles", false ) )
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 0 3"
+			} )
 		}, new FormLayoutConstraints( null ) {
 			"location": new java.awt.Point( 0, 0 )
 			"size": new java.awt.Dimension( 960, 495 )

flatlaf-theme-editor/src/main/resources/com/formdev/flatlaf/themeeditor/FlatLafUIKeys.txt

@@ -1039,7 +1039,6 @@ TitlePane.inactiveBackground
 TitlePane.inactiveForeground
 TitlePane.maximizeIcon
 TitlePane.menuBarEmbedded
-TitlePane.menuBarResizeHeight
 TitlePane.menuBarTitleGap
 TitlePane.menuBarTitleMinimumGap
 TitlePane.noIconLeftGap
@@ -1071,7 +1070,6 @@ TitlePane.small.iconifyIcon
 TitlePane.small.inactiveBackground
 TitlePane.small.inactiveForeground
 TitlePane.small.maximizeIcon
-TitlePane.small.menuBarResizeHeight
 TitlePane.small.menuBarTitleGap
 TitlePane.small.menuBarTitleMinimumGap
 TitlePane.small.noIconLeftGap