Okay, this might be a claws issue, it might be a window manager issue (xfce4), but I don't see it in any other application. I have claws mail set to auto-start with my desktop session, but while I can read (and either via menu or control-o) move emails between folders, "drag and drop" moving of emails doesn't work. (you drag to destination, but it 'snaps back' and doesn't move). Close claws and restart (in the same session) and it's works fine. So it looks like some sort of interaction between xfce4 starting up and claws starting up. Annoying, but tolerable. Has anyone else seen this?