packages/main-nav/src/js/module.js
function attachHandler() {
			var handler = rawHandler.call( element, window.event );
			if ( handler === false ) {
				window.event.returnValue = false;
				window.event.cancelBubble = true;
			}
			return( handler );
		}
function attachHandler() {
			var handler = rawHandler.call( element, window.event );
			if ( handler === false ) {
				window.event.returnValue = false;
				window.event.cancelBubble = true;
			}
			return( handler );
		}
function attachHandler ( ) { var handler = rawHandler . call ( element , window . event ) ; if ( handler === false ) { window . event . returnValue = false ; window . event . cancelBubble = true ; } return ( handler ) ; }
Make sure attachHandler is also going to work
Make sure attachHandler is also going to work