Closing this request. 11.2 which is in experimental [11.2] is better suited for bookworm: it has a smaller diff with what's in stable now. However, since 11.2 has some other problems ( #1035913 ), I'll do more work in the coming days and hope to come up with an ever better candidate for bookworm. Sorry for the noise.
Bye, Joost [11.2] https://tracker.debian.org/news/1430982/accepted-doc-debian-112-source-into-experimental/