Make something happen when a window gets focus

Is there a way to move a menu from one window to another or make it visible/invisible when the window gets or loses focus?

[bob]

Yes. A Mapped key using Menu State Actions to Load on Window:Current and Unload on Window: all w/o Current, and then have this execute when you switch to each slot

Thanks, I was able to get my DPS indicator to switch screens to show me which screen was active. My setup is purring like a kitten now.