The development team has released a public Trello board. Following the MP4 Mania UPD (3.2.x), version 4.0 is expected in Q2 2025 with these features:
The old WinForms look has been replaced with a modern Qt6 interface. The MP4 Mania UPD introduces a dark mode, draggable queue lists, and a live preview window. mp4 mania upd
If you have a library of thousands of MP4 files, you don't need to re-encode everything. However, you should consider rewrapping your most critical files. The update is backward-compatible at the container level, but to get the new speed features, the file must be rewritten with the new structural boxes. The development team has released a public Trello board
Step-by-step to update an existing MP4: