public static void setUseNativeWindowDecorations( boolean enabled ) {
		UIManager.put( "TitlePane.useWindowDecorations", enabled );

		if( !(UIManager.getLookAndFeel() instanceof FlatLaf) )
			return;

		// update existing frames and dialogs
		for( Window w : Window.getWindows() ) {
			if( isDisplayableFrameOrDialog( w ) )
				FlatRootPaneUI.updateNativeWindowBorder( ((RootPaneContainer)w).getRootPane() );
		}
	}
Sets whether native window decorations are enabled.
<p>
Existing frames and dialogs will be updated.

@since 1.1.2
flatlaf-core/src/main/java/com/formdev/flatlaf/FlatLaf.java