public static void registerSystemScaleFactors( JFrame frame ) {
		registerSystemScaleFactor( frame, "alt shift F1", null );
		registerSystemScaleFactor( frame, "alt shift F2", "1" );

		if( SystemInfo.isWindows ) {
			registerSystemScaleFactor( frame, "alt shift F3", "1.25" );
			registerSystemScaleFactor( frame, "alt shift F4", "1.5" );
			registerSystemScaleFactor( frame, "alt shift F5", "1.75" );
			registerSystemScaleFactor( frame, "alt shift F6", "2" );
			registerSystemScaleFactor( frame, "alt shift F7", "2.25" );
			registerSystemScaleFactor( frame, "alt shift F8", "2.5" );
			registerSystemScaleFactor( frame, "alt shift F9", "2.75" );
			registerSystemScaleFactor( frame, "alt shift F10", "3" );
			registerSystemScaleFactor( frame, "alt shift F11", "3.5" );
			registerSystemScaleFactor( frame, "alt shift F12", "4" );
		} else {
			// Java on macOS and Linux supports only integer scale factors
			registerSystemScaleFactor( frame, "alt shift F3", "2" );
			registerSystemScaleFactor( frame, "alt shift F4", "3" );
			registerSystemScaleFactor( frame, "alt shift F5", "4" );

		}
	}
register Alt+Shift+F1, F2, ... F12 keys to change system scale factor
flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/DemoPrefs.java