Writing custom tag with beet modify not showing with beet info and ffmpeg

[laker-93]

Hello

I am using beet modify to write a custom tag to a file:

beet modify Minitx dup=1

This seemingly writes the tag successfully:

root@4787cef4963b:/# beet modify Minitx dup=1
Modifying 1 items.
Skee Mask - C - Minitx
  dup: 1
Really modify, move and write tags? (Yes/no/select) Yes

I can see the new "dup: 1" tag set with beet edit --all.

However I do not see the custom tag with beet info.

Similarly, when I use ffmpeg to inspect the tags of the track, I do not see the new tag in the output. This is a problem for me as I'm using beets to set custom tags which I then want Navidrome to pick up and display in the UI. Navidrome used ffmpeg to parse tags so currently I cannot extract my custom tags in navidrome from the output of ffmpeg.

ffprobe -show_format -print_format json -i /music/Skee\ Mask/C/07\ -\ Minitx.mp3

        "tags": {
            "title": "Minitx",
            "artist": "Skee Mask",
            "track": "7/11",
            "album": "C",
            "disc": "1/1",
            "date": "2024-01-04",
            "genre": "Ambient",
            "TBPM": "0",
            "compilation": "0",
            "language": "eng",
            "lyrics-XXX": "",
            "TIPL": "arranger",
            "album_artist": "Skee Mask",
            "artist-sort": "Skee Mask",
            "TDOR": "2024-01-04",
            "Script": "Latn",
            "TMED": "Digital Media",
            "ARTISTS": "Skee Mask",
            "ALBUMARTISTS": "Skee Mask",
            "ARTISTS_SORT": "Skee Mask",
            "ALBUM_ARTISTS": "Skee Mask",
            "Artist Credit": "Skee Mask",
            "ARTISTS_CREDIT": "Skee Mask",
            "ALBUMARTISTSORT": "Skee Mask",
            "ALBUMARTISTS_SORT": "Skee Mask",
            "ALBUMARTISTS_CREDIT": "Skee Mask",
            "Album Artist Credit": "Skee Mask",
            "MusicBrainz Album Status": "Official",
            "MusicBrainz Album Release Country": "XW",
            "comment": "Visit https://skeemask.bandcamp.com",
            "MusicBrainz Album Type": "album",
            "MusicBrainz Album Id": "9131b04f-c997-4e5a-9273-563e9c67e8b8",
            "MusicBrainz Artist Id": "2b3e25ba-983e-44ac-9def-907e03910cd2",
            "MusicBrainz Album Artist Id": "2b3e25ba-983e-44ac-9def-907e03910cd2",
            "MusicBrainz Release Group Id": "9805e30a-80ec-45be-bee9-d42eab66565a",
            "MusicBrainz Release Track Id": "266c59b9-4847-41e1-8ff2-7fbbf9745695"
        }

I've tried to use beet write to write the tag information to the file but still no luck. Any tips on how I can write this custom tag and have ffmpeg see it?