I discovered feishin today on Github. It's made by the creator of sonixd, another great jellyfin/subsonic desktop client.
Works super smooth. Feels basically like Spotify desktop, but FOSS.
The only missing feature for me is the ability to cache songs for offline playback.
It still has bugs with the version 0.3.0 of you ask me... I use Navidrome and Sometimes music won't play until i switch songs back and forth a couple of times... Sonixd still provides smooth experience, I'm waiting for feishin to iron out the bugs