Stickers don't seem to get forwarded to WA

[vaaski]

Hey, I've set up a Telegram <-> Matrix <-> WhatsApp bridge to avoid using WhatsApp.
I can receive stickers from WA just fine, but the ones I send from Telegram just don't show up in WA at all. They appear in Matrix just fine.

I am pretty new to this whole Matrix stuff, so let me know if you need any more information.

Here is the source of the sticker as it arrives from TG in Matrix

{
  "type": "m.sticker",
  "sender": "@telegram_270144403:redacted.local",
  "content": {
    "body": "👍 (thumbs up sign)",
    "external_url": "https://t.me/c/1234567890/255",
    "url": "mxc://redacted.local/PrtqxXlABlYlSmjhXtBrEspV",
    "info": {
      "mimetype": "image/webp",
      "size": 26346,
      "thumbnail_info": {
        "mimetype": "image/webp",
        "size": 26346,
        "h": 256,
        "w": 256,
        "fi.mau.telegram.sticker": {
          "alt": "👍",
          "id": "1644927493175509158",
          "pack": {
            "id": "1644927493175508997",
            "access_hash": "-5785660578498188602"
          }
        }
      },
      "thumbnail_url": "mxc://redacted.local/PrtqxXlABlYlSmjhXtBrEspV",
      "h": 256,
      "w": 256,
      "fi.mau.telegram.sticker": {
        "alt": "👍",
        "id": "1644927493175509158",
        "pack": {
          "id": "1644927493175508997",
          "access_hash": "-5785660578498188602"
        }
      }
    },
    "fi.mau.telegram.source": {
      "space": 1234567890,
      "chat_id": 1234567890,
      "peer_type": "channel",
      "id": 255
    }
  },
  "origin_server_ts": 1728136030000,
  "unsigned": {
    "membership": "join",
    "age": 135
  },
  "event_id": "$5kgDZ3hpJl8JXIpExiKpwTixUQKFnVL_hCBn65O96uw",
  "room_id": "!hvEBpftVjjiksoGJWC:redacted.local"
}