Group DMs have no name

[robintown]

Steps to reproduce

This needs to be checked again:

1. Start a new DM with at least 2 other people
2. Look at the room list

What also (actually) does caue the issue:

1. create a dm room
2. give the room a name
3. change the room name to empty. (remove the name and click save) (or set the state event manually)
4. the m.room.name state event content will be {name: ""}
5. check the room name and the room list (you will see what is presented below)

Outcome

What did you expect?

If I invite Alice and Bob to the room, the name shown in the client should be "Alice and Bob"

What happened instead?

The name is empty:

Operating system

NixOS 25.05

Browser information

Firefox 145.0

URL for webapp

develop.element.io

Application version

Element version: dd89cee-js-c7a75c882479 Crypto version: Rust SDK 0.14.0 (c3b7918), Vodozemac 0.9.0

Homeserver

Synapse 1.135.2

Will you send logs?

No

[toger5]

I am not sure this is realted to the number of participants. I do have the same situation with a real DM (just two m.room.member) events.

Those are really old chats. Can this be a room version issue?

[Half-Shot]

I'm guessing the string comes from https://github.com/vector-im/riot-web/blob/4a381c2a105c4f26d8e6975ee53c75b7ad204ad7/src/hooks/useRoomName.ts#L26, which happens if Room.name is falsey.

[toger5]

name is "name": "" for the rooms I am seeing issues with.

[Half-Shot]

Right, that's why then. The hook is using || so it will fallback correctly. The name being "" is strange though, do you have a m.room.name with a value of "" in the room?

[toger5]

So it probaly is caused by useRoomName() being called wihtout OOBName?
useRoomName(userName)< would be what we need?

[toger5]

The name being "" is strange though, do you have a m.room.name with a value of "" in the room?

yes exactly

[toger5]

cannot delete it however since synapse is getting unhappy:

[toger5]

This also causes issues on element X with the profile picture I think.

@robintown can you check if you have issues with the PB in the respective rooms or if this is unrealted?