(Tested against Default, local installed client.)
General symptom: Character is getting logged-off, but the client seems to wait for some confirmation, from the server I take it, that never comes. Ergo: staying in game mode instead of dropping back to the player log-in stage. Effectively forcing the client to be restarted.
- Logging off a character shortly after is was logged-in, but without doing anything other than walking around a bit. In general seems to not fail the first time*, but seems to have a really high change of failing on the second* log-off attempt.
*) After the client start-up, or so it seems at the moment.
(note: this includes a re-login of the player and character.)
Old old bug if I'm correct.

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Unable to duplicate (so far) in:
- UNION v7.2c ... (Mmm. Outside that is. Just run into a client lock-up when turning a character to sleep inside a cave.)