Image subtext not displayed

[christoph-heiss]

Bug Description

Hi!

At least on iOS fluffychat 1.23.0, any text part of a message event which also contains a file/image, the text is not displayed.

While Element nor fluffychat allow you to create such events, using bridges such like mautrix-signal they can be easily encountered.

For reference, the Element web app handles them correctly and does indeed display both the image and text.

Steps to Reproduce

Using mautrix-signal:

1. Go to the "Note to Self" chat on the Signal mobile/desktop app
2. Send an image with text directly attached.
3. Check the message on fluffychat, which will not have the text display

Not sure how to reproduce it without a bridge.

Expected Behavior

That both the text and the image are displayed for such an event.

App Version

1.23.0

Additional Platform Information

iOS (iPhone 12 Pro)

Additional Context

The decrypted, raw content of such a message:

{
  "content": {
    "body": "foo bar",
    "fi.mau.double_puppet_source": "mautrix-signal",
    "fi.mau.double_puppet_ts": 0,
    "file": {
      "hashes": {
        "sha256": "xxx"
      },
      "iv": "xxx",
      "key": {
        "alg": "A256CTR",
        "ext": true,
        "k": "xxx",
        "key_ops": [
          "encrypt",
          "decrypt"
        ],
        "kty": "oct"
      },
      "url": "mxc://y.z/xxx",
      "v": "v2"
    },
    "filename": "test.jpeg",
    "info": {
      "blurhash": "xxx",
      "h": 1600,
      "mimetype": "image/jpeg",
      "size": 195573,
      "w": 900,
      "xyz.amorgan.blurhash": "xxx"
    },
    "m.mentions": {},
    "msgtype": "m.image"
  },
  "event_id": "xxx",
  "origin_server_ts": 0,
  "room_id": "!x:y.z",
  "sender": "@w:y.z",
  "type": "m.room.message",
  "unsigned": {}
}

Where foo bar would be the text attached to the image.