Earlier quoted context omitted.
Navidrome [0] has been a solid replacement for me. It has all the features I want aside from Keycloak/generic oidc integration, and the author is very responsive. 0: https://github.com/navidrome/navidrome
Second this. Navidrome is an impressive piece of work. Solid UX, decent core feature set, good performance, trivial to deploy (it's a single statically linked Go binary). I've definitely had some glitches with playback and so forth, so it's not flawless, but it's still very good.
Other than a few UX bugs I haven't had any real issues, so I'm happy with it.
0: https://github.com/lijinke666/react-music-player
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