Waveform object in voice message contained only nulls

[Half-Shot]

Steps to reproduce

• Record a voice message in Element Web

What happened?

The MSC in matrix-org/matrix-spec-proposals#3246 appears to only allow integer numbers in the waveform array, but some events sent by element-web include nulls.

What did you expect?

An array containing numbers. Otherwise, the event is incompatible with the spec.

Operating system

Linux

Application version

1.8.1

How did you install the app?

Internal Testing Server

[Half-Shot]

This also causes Element Android to fail to render the event at all, although other Element Web instances seemed to be able to render and play the event (amazingly, with a proper waveform).

The event in question looks like:

{
  "content": {
    "body": "Voice message",
    "info": {
      "duration": 6616,
      "mimetype": "audio/ogg",
      "size": 16861
    },
    "msgtype": "m.audio",
    "org.matrix.msc1767.audio": {
      "duration": 6616,
      "waveform": [
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null,
        null
      ]
    },
    "org.matrix.msc1767.file": {
      "mimetype": "audio/ogg",
      "name": "Voice message.ogg",
      "size": 16861,
      "url": "mxc://redacted"
    },
    "org.matrix.msc1767.text": "Voice message",
    "org.matrix.msc3245.voice": {},
    "url": "mxc://redacted"
  },
  "origin_server_ts": 1629192939655,
  "sender": "@redacted",
  "type": "m.room.message",
  "unsigned": {
    "age": 581
  },
  "event_id": "$LsQ6INnif5DoDUKzP5UvtD9UmWr3O8c-XSLuJEey77Q",
  "room_id": "!redacted"
}

[SimonBrandner]

I don't think I am able to repro

[SimonBrandner]

NVM, I can repro on FF

[SimonBrandner]

I also don't see any waveform when recording