@blogdiva Would IceCat be viable at all as some kind of base? It's basically Firefox ESR just with Mozilla and FireFox branding removed/changed.
https://en.wikipedia.org/wiki/GNU_IceCat
https://jessie.nabein.me/blog/consider-using-gnu-icecat-instead-of-firefox.html
@jessienab Librewolf would be the de facto model to follow. it's degoogled AND stripped most of Mozilla's commercialized garbage.