[Menus] Gray out submenus where all children menu items are disabled

[pedropaulosuzuki]

Description
Since we disable all the children menu items, it makes sense to at least gray out the submenu as well. The submenu should still be clickable and expandable. I'm not completely sold on the idea, but I think it's worth discussing.

Additional context

[cameronwhite]

Does this case only happen when there are no images open, or are there some other cases where menus end up like this?

I don't mind the idea of greying out the menus if nothing is available underneath

[pedropaulosuzuki]

Does this case only happen when there are no images open, or are there some other cases where menus end up like this?

As far as I remember, only when there are no images open.