navigating menus of guest windows using keyboard doesn't work

[Soren Harward]

When I have a guest window in focus but the keyboard uncaptured, I cannot navigate the menu using the keyboard. For example, I should be able to hit <alt>+<M> and pull down the "Machine" menu, or hit <alt>+<D> and pull down the "Devices" menu. Neither of these work. I can activate actions within the menus, like hitting <host>+<n> to get session information. But I can't get to the menus themselves.