Show hints for opened menu within active application and its menu bar

[dexterleng]

• Does not work for menus belonging to non-active applications (dock, extra menu bar)
• Switched to global input listener + non-key window

Does not seem to work when trying to expand the "Open with..." menu item in Finder. Does not work correctly when a submenu closes. Hints are shown for the whole window instead of the parent menu Hold Space to deactivate is broken.