These calls were originally introduced to ensure that any stale users were cleaned up regularly. This is quite an expensive process to run on every `GET /presence/get` call, and will also cause errors during readonly mode.
Since the original introduction of this logic, we added the `Jobs::PresenceChannelAutoLeave` which runs every minute. That should be enough to clean up any stale users.
Note that users which explicitly `leave` a channel are still removed immediately. This auto_leave logic just takes care of clients which have disappeared without leaving.
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