Great except for one major problem (in my opinion): it does not keep up to date with the Jellyfin library (content, favourites, playlists) with performing a manual full sync in the app and even then playlists and favourites mismatches seem to often persist.

I’ve started using Wavio. It is partially vibe coded but it is open source. I used to use Symphonium but I didn’t like how it does (or rather doesn’t) keep in sync with the Jellyfin library without manual intervention.