private static boolean overlapsHeavyWeightComponent( Component parent, Rectangle r ) {
		if( !parent.isVisible() || !r.intersects( parent.getBounds() ) )
			return false;

		if( !parent.isLightweight() && !(parent instanceof Window) )
			return true;

		if( parent instanceof Container ) {
			Rectangle r2 = new Rectangle( r.x - parent.getX(), r.y - parent.getY(), r.width, r.height );
			for( Component c : ((Container)parent).getComponents() ) {
				if( overlapsHeavyWeightComponent( c, r2 ) )
					return true;
			}
		}

		return false;
	}
Checks whether the owner component returns a tooltip location in
JComponent.getToolTipLocation(MouseEvent).
flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatPopupFactory.java