This is a bit niche, but I do a lot of archiving of recordings of modern and old sessions of traditional folk dance. To make categorizing them easier, I've put together a specification for tagging these dances with the various metadata that is somewhat unique to called folk dances:

https://datatracker.ietf.org/doc/draft-swhited-contra-tags/

Though this draft was meant for Matroska tags (which are widely used in archival work), it also includes a section about how to use it with Vorbis Tags and other systems as I frequently have existing recordings that I don't want to convert.

I would like to request that the tags from this document be added to the tags list so that they can be auto-completed in the interface.

I have submitted a PR in case this is desirable, but I fully understand that this is a niche and likely low-priority issue and that everyone is most likely busy with Picard 3 work at the moment, so no pressure.

Thanks for making this excellent tagger, I use Picard heavily and very much appreciate all the work you put into it!