static synchronized void uninstall() {
		if( instance == null )
			return;

		MenuSelectionManager.defaultManager().removeChangeListener( instance );
		instance.uninstallEventQueue();
		instance = null;
	}
Improves usability of submenus by using a
<a href="https://height.app/blog/guide-to-build-context-menus#safe-triangle">safe triangle</a>
to avoid that the submenu closes while the user moves the mouse to it.

@author Karl Tauber
flatlaf-core/src/main/java/com/formdev/flatlaf/SubMenuUsabilityHelper.java