Somehow I managed to screw up the linking between some NetAtmo channels and the respective items. I’m surely never linked all of these items to the one channel, though OH2 now is resolute and don’t let me delete it via paper UI anymore:
When I try to unlink, I get the following message:
Removing the thing didn’t help - problems persists when I install the thing again.
What can I do to get rid off the bad linking?