Mine is Strawberry since it has a ton of options and plays a ton of formats. It's also (distant) fork of Amarok 1.4 and integrates well with KDE Plasma. I'm curious what other people are using these days. What's your favorite player?
Navidrome’s web player is actually pretty good and I could totally live with it if third party clients weren’t an option. Supersonic is more performant when loading 1800+ song playlists though, and infinite scrolling instead of the paginated web library is really nice.