Hmm interesting. I am on wayland for sure, but I tried to make it work for an hour yesterday.

How I noticed it:

I started an install process in pamac gui, then I tabbed to browser window and typed some stuff. Pamac finished downloads and asked for confirmation, the default being cancel and me typing ENTER cancelled it. Mouse was on the browser window and each app was on a different monitor.

I was able to repeatedly reproduce it by doing the same. I have set focus stealing prevention to high, which is described as focus only being stolen when the same type of window is active.

Is my issue maybe that both ran through xwayland? I’ll have to check that later.