I just tagged Media.Ui the stable versions 2.0 and 3.0 after the previous betas seemed fine and only one PHP 8.4 related bugfix was merged Releases · Flowpack/media-ui · GitHub.
Therefore this subproject can be considered finished.
As the funding for this topic covered about 55% of my invested time as I spent a lot of time on modernising, testing and increasing test coverage. Any additional sponsoring would help a lot to continue on this path.
Thx again for everyone who helped and supports this project.