I find that when a sync is in process (upload) the UbuntuOne app refuses to quit. It doesn't seem to hang for me (it remains responsive), it just ignores the quit command and I have to force quit.
I find that when a sync is in process (upload) the UbuntuOne app refuses to quit. It doesn't seem to hang for me (it remains responsive), it just ignores the quit command and I have to force quit.