Audio attachments in ActivityPub posts are silently dropped when posted to Bluesky

[dos1]

A post with audio file (as can be uploaded with e.g. Mastodon) reaches Bluesky with no audio and no mention that the audio file was supposed to be there.

Example:
https://social.librem.one/@dos/113499714989458870 -> https://bsky.app/profile/dosowisko.net/post/3lb5zyx3e4f22

Since AFAIK Bluesky doesn't allow audio files to be shared, I'd expect the bridge to at least put a card with original file (or post) linked, so the media content is still accessible by the reader on Bluesky. The bridge could potentially turn audio files into videos with empty visual content, although I'm not sure if it's worth the effort given rather short duration limit for videos on Bluesky.

[snarfed]

Ooh, audio, exciting!

Here's what the AS2 attachment looks like:

  "attachment": [
    {
      "type": "Document",
      "mediaType": "audio/mpeg",
      "url": "https://social.librem.one/system/media_attachments/files/018/622/172/original/41b8341a33f5cb72.mp3",
      "name": null,
      "blurhash": null
    }
  ],