I'll probably give this a try, thanks!
But I'm confused about your explanation: you say you didn't wanna contribute to the existing project at you didn't know dart/flutter. Then you end up creating your project from scratch, using dart/flutter to learn dart/flutter. Why not just contribute to the existing project, or fork it, instead of reinventing the (same) wheel?
You kinda want it to be based on Firefox, as the only other option is chrome. The forks already strip out all the mozilla bullshit, it'll just be more work to strip out all the AI nonsense.
I'm mainly familiar with librewolf, it's not just stripped of nonsense but also hardened by default. Actually so much so that I stayed on Firefox as it was too much effort (so far) to "unharden" all the aspects I didn't want or need.