@sun @lain @pwm as for maintenance: I have Debian set to auto patch and that's it. I shouldn't need to touch anything ever. Unless somehow I run out of disk space from users swarming my server and their messages getting piled up before the auto-purge-old-messages kicks in (mine's configured for 7 days)

Normal Delta Chat: no messages stored on server at all (except while waiting for client to download them).

after enabling Multi-device Delta Chat for your account: the clients don't delete messages off server automatically after downloading, but let the server purge them on its own schedule as IMAP doesn't have a way to tell which client did what // track their access to emails.

Messages on the server are always encrypted anyway and can't be read by anyone