There is a contextmenu event fired when the user right clicks or long presses (with touch) to show a context menu (Note #279 proposes adding this event to UI Events). There is however no notification about the closing of that menu. Developers typically call preventDefault() on the contextmenu event to create a custom menu, however they have to implement custom logic to try to detect under what circumstances it should close. There are many scenarios under which a contextmenu should be closed, that would be easier to handle given a single event to listen for:

• Escape key pressed
• When focusing any other window
• Clicking outside of the browser window
• When interacting with touch it is common to initiate a contextmenu after a long press. However, if the item being pressed is also draggable than a subsequent drag of the finger can be used to initiate a drag which implicitly cancels the contextmenu.

I propose adding a contextmenuclose (or contextmenucancel or contextmenudismiss) event which will be dispatched under the conditions when the platform would close a native contextmenu.