Jellyfin 12.0 introduces native support for books and comics, integrating core features from the previously required Bookshelf plugin. The server can now read OPF and ComicInfo metadata files, generate covers for EPUB and comic archives, and extract page counts for PDFs and chapter information for audiobooks.
The update features a significant database overhaul. Playlists and collections are now stored as individual data rows rather than single blocks, which improves loading and editing speeds for large lists. Performance gains also apply to 'Continue Watching', 'Next Episode', and artist search pages.
The versioning system has changed, removing the '10.' prefix to reflect the scale of recent architectural updates. The team plans to update the major version number annually. Users can upgrade directly from versions 10.10.7 and 10.11.x, though those on older versions must first update to 10.10.7.
New features include multi-version support for TV series, allowing different cuts or resolutions of the same episode to be grouped. The 'Modern' UI layout is now the default for desktop and mobile, while the old interface is renamed 'Legacy'.
Technical updates include the transition to FFmpeg 8.1 for transcoding, support for VobSub subtitle streams, and fixes for HLS audio-video synchronization. The release also addresses security vulnerabilities related to path traversal and cross-site scripting (XSS).
