When menus are clamped to the window bounds,
its was possible not to have an active menu-item under the mouse,
Making Ctrl+S,Enter not completely reliable.
Changes needed to support this are:
- menu item is activated on popup menus
(to avoid relying on mouse-over)
- moving mouse away from menu items only de-activates when over a new menu-item.
- Mouse clicks are ignored if they are not directly over the menu item.
47e7ce696c