I stumble on this often and forever. Please fix it:

Problem:
When accessing the Window menu item it only displays items like 'big picture' and 'small mode', which is fine. However it should also contain a list of all the windows the application is displaying on screen or is minimized. Steam does not do this. Therefore if say your friends list window is buried behind a bunch of other windows there is no way to access it without moving things out of the way.

I suspect the root of this issue is also responsible for not being able to use command-tilda/accent to swap between application windows.