Jonathan T on Nostr: I'm not at my Mac but try doing a Command-click or Option-click on the object in the ...

I'm not at my Mac but try doing a Command-click or Option-click on the object in the background window to see if that works.

The difference is that you are being prevented from doing something potentially destructive. An accidental mouse click (or Return/Enter key press) isn't going to steal focus from your active window and activate something in the background instead just because you moved your mouse offscreen or onto another window unintentionally.