Well, this is strange. The issue is gone. I'm not sure when, but I think since I reinstalled mate-applets after playing with it a bit (compiling from source etc.), the applet behaves exactly as expected now. So maybe there was an update that maybe wasn't applied properly or something like that. I'm puzzled. I'm sure it was there before. It certainly was there when I was still using MATE 1.6 under LMDE, and it also was there not long ago. I'm quite sure I have seen it when I had installed mate-applets from source (via apt-src), but then it just... vanished.
I guess this means the issue can be closed then, and no further testing is needed... -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org