private static void hideSnapshot( Map<JLayeredPane, JComponent> map ) {
		// remove snapshots
		for( Map.Entry<JLayeredPane, JComponent> e : map.entrySet() ) {
			e.getKey().remove( e.getValue() );
			e.getKey().repaint();
		}

		map.clear();
	}
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.
flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatAnimatedLafChange.java