Activities view shows all windows on external monitor at once
Even with "current workspace contains additional displays" is checked (I hope that's what it is called, I had to guess from the German translation), the activities view shows all windows placed there at once. This is in contrast to the standard display, where it only shows windows from the currently selected workspace. Windows on external displays should be shown in the same way like on the standard display. (The behavior could be configurable, but at least it should be the same on all displays.)