Failed to change power level in certain channels

[dom96]

Steps to reproduce

1. https://app.element.io/#/room/#nim-lang:matrix.org
2. Trying to give a member moderator privileges, done via searching for their nick, clicking their account then using the dropdown.

Outcome

What did you expect?

User gets mod privs

What happened instead?

This works in other channels. For some reason in this channel specifically it fails :/

Operating system

Windows

Browser information

Firefox

URL for webapp

app.element.io

Application version

No response

Homeserver

No response

Will you send logs?

Yes

[t3chguy]

This is the actual error:

2021-11-14T16:29:58.766Z E Failed to change power level M_BAD_JSON: "@freenode_yglukhov[i]:matrix.org": '0' is not of type 'integer'

[ghost]

Is there any workaround or fix for this issue? The channel in question is the main bridged Matrix channel of our Nim community (bridged to Discord and IRC). It's quite troublesome for us as we currently only have one active admin in this channel, and they don't always have time to remove spam. Maybe it's possible to promote admins some other way?

[PMunch]

Is the Nim channel the only one affected? Judging by that error it seems like all channels should have the same error..

[ghost]

@PMunch I doubt all channels have the same exact user joined (@freenode_yglukhov[i]:matrix.org) :)

[PMunch]

Oh that's what it meant? To be honest that error message doesn't make much sense, it first shows their username, then complains that '0' is not an integer

[t3chguy]

Cannot reproduce

[dom96]

Just tried again and still can't change power levels in that channel. Anything else that I can do to help repro? I'm not sure this is related to that specific username.

[t3chguy]

So that room has a broken power levels event

{
  "content": {
    "ban": 50,
    "events": {
      "im.vector.modular.widgets": 50,
      "m.room.avatar": 100,
      "m.room.canonical_alias": 100,
      "m.room.encryption": 100,
      "m.room.history_visibility": 100,
      "m.room.name": 100,
      "m.room.power_levels": 100,
      "m.room.server_acl": 50,
      "m.room.tombstone": 100,
      "m.room.topic": 100
    },
    "events_default": 0,
    "invite": 0,
    "kick": 50,
    "redact": 100,
    "state_default": 100,
    "users": {
      "@appservice-irc:matrix.org": 100,
      "@dom96:matrix.org": 100,
      "@freenode_yglukhov[i]:matrix.org": "0",
      "@uran:matrix.org": 100
    },
    "users_default": 0
  },
  "event_id": "$162405382075982TABhT:matrix.org",
  "origin_server_ts": 1624053820674,
  "room_id": "!EtGqjSRNQoJCbpCJSF:matrix.org",
  "sender": "@dom96:matrix.org",
  "state_key": "",
  "type": "m.room.power_levels",
  "unsigned": {
    "replaces_state": "$162405381975981bMSPl:matrix.org",
    "age": 18455146100
  },
  "user_id": "@dom96:matrix.org",
  "age": 18455146100,
  "replaces_state": "$162405381975981bMSPl:matrix.org"
}

"@freenode_yglukhov[i]:matrix.org": "0", should be 0 not "0"

Given that Synapse is happy to return these, it should also be happy to accept them. I'd suggest this be raised on the Synapse repo. Requiring that all clients repair all power levels events seems the wrong balance.

[t3chguy]

Closing in favour of matrix-org/synapse#12538