The creator of Floorp posted a reponse to this: https://blog.ablaze.one/4125/2024-03-11/

TLDR posted by the creator: creator:

To put it simply, the current Floorp, including forks, will end the moment I stop maintaining it, so to prevent that from happening, I have prohibited forks. The idea is to solve the user’s concern about code transparency by tightening the license when returning to open source, and to create a sustainable Floorp by giving them the choice of paying money or helping with the coding.

Unfortunately a lot of this seems in reponse to Midori, a seemingly hostile fork with a pretty suspcious website.