Wikimedia Bugzilla is closed!

Currently, the mouse event handling in phantoms is:

// mouseenter on the protectednode
ve.ce.ProtectedNode.prototype.onProtectedMouseEnter = function () {
	if ( !this.root.getSurface().dragging ) {
		this.createPhantoms();
	}
};

// mousemove on the surface, bound by createPhantoms and unbound by clearPhantoms
ve.ce.ProtectedNode.prototype.onSurfaceMouseMove = function ( e ) {
	var $target = $( e.target );
	if (
		!$target.hasClass( 've-ce-protectedNode-phantom' ) &&
		$target.closest( '.ve-ce-protectedNode' ).length === 0
	) {
		this.clearPhantoms();
	}
};

// mouseout on the surface, bound by createPhantoms and unbound by clearPhantoms
ve.ce.ProtectedNode.prototype.onSurfaceMouseOut = function ( e ) {
	if ( e.toElement === null ) {
		this.clearPhantoms();
	}
};

Issues:
* the mousemove handler seems to permit moving the mouse directly to a different ProtectedNode without causing the phantoms to be cleared
* the mouseout handler uses e.toElement, which is a poorly documented property that's allegedly IE-only
* it's generally very difficult to reason about what this code does or convince oneself that it does something reasonable