From what I understand, while it's arguably a massive update, the base functionality you expect from version 2.x still exists and should just work immediately.
Another difference would be that 32-bit is fully dropped, but they claimed it never actually worked properly for the past several years to begin with.
https://github.com/jellyfin/jellyfin-mpv-shim/releases/tag/v3.0.0
Also it's probably a requirement to update to v3 if you also use locally-installed Jellyfin server v12, which was already auto-updated to this bucket an hour ago, bd058e3.
From what I understand, while it's arguably a massive update, the base functionality you expect from version 2.x still exists and should just work immediately.
Another difference would be that 32-bit is fully dropped, but they claimed it never actually worked properly for the past several years to begin with.
https://github.com/jellyfin/jellyfin-mpv-shim/releases/tag/v3.0.0
Also it's probably a requirement to update to v3 if you also use locally-installed Jellyfin server v12, which was already auto-updated to this bucket an hour ago, bd058e3.