Left DM rooms rebridge on next contact sync

[Half-Shot]

After a period of time, or after startup users are seeing DM rooms they have left get re-bridged which is quite annoying for them.

[mulles]

Work around, ask the admin of the signal group or DM to kick you out of the room.

[maltee1]

Signald doesn't seem to have a way to delete a user. You can set autocreate_contact_portal to false to prevent contact portals from popping up by themselves, but that might be desired behavior in other situations.
Otherwise mautrix-signal would have to keep a list of contacts that are in signald but that users left the portal of. I don't think that's a good idea.
Or you can file an issue with signald to allow deleting contacts.