I had manually added a certain callsign to the station list, to locally store a MSG waiting for that op.

That done, some time later, I decided to again remove that station.

In the UI, I opened that line's context menu and saw, among others, two options: "clear" and "clear all".

I chose "clear".

My expectation: That station would be removed from the window.

Actually seen: All stations were removed from that window.