Menu bar for the editor

1. Open menu bars in different editors.
2. Navigate menus using mouse (hover).
3. Navigate menus using keyboard (arrow keys, Esc).
4. You should be able to seamlessly move from mouse navigation to keyboard navigation.
5. Use Alt+F9 to focus the menu bar.
6. Use Esc to get back to the editing root.
7. Make sure menu bars that open with not enough space to the bottom display to the top of the button.
8. Make sure menu bars that open with not enough space to the right display to the left of the button (this reverses in RTL).