[Matrix] Matterbridge always uses the latest room specific display name everywhere

[Mikaela]

Describe the bug

When I change my room display name in one room, I suddenly see it as my name through the Matterbridge instance everywhere.

To Reproduce

1. Bridge two Matrix rooms
2. /devtools, explore room state, m.room.id, change your display name, send the event
   • it may also be possible to use /myroomnick
3. start talking in another room
4. observe your name having changed there too through matterbridge.

Expected behavior

I expect to see the original name in where I didn't change my name.

Screenshots/debug logs

I cannot debug logs now.

Environment (please complete the following information):

• OS: Debian 10 GNU/Linux
• Matterbridge version: https://github.com/42wim/matterbridge/releases/tag/v1.20.0 (I cannot SSH right now)

Additional context

• I am assuming Element is being used as the Matrix client.
• This may also affect avatars, but I don't have a Discord where I would see that.
• If I am missing something important from this issue to help with reproduction, please let me know and I will add it ASAP.

[lukaszpolowczyk]

Question / Suggestion:
Will it be possible to set the username for all rooms in Space at once?

[42wim]

It's not supported yet upstream, so maybe when the matrix API has support for this we can integrate it.
matrix-org/matrix-spec-proposals#3189

[tulir]

Per-room profiles are supported upstream, they have existed since the beginning. That MSC is primarily for space-wide profiles.

there is no way to fetch the nick per room using the matrix API ?

GET /_matrix/client/r0/rooms/!roomid:foo.bar/state/m.room.member/@user:example.com (aka mc.StateEvent("!roomid:foo.bar", "m.room.member", "@user:example.com", &outContent)) will return the membership event content, which includes the room-specific displayname and avatar.

{
  "membership": "join",
  "displayname": "user",
  "avatar_url": "mxc://example.com/mediaid"
}