Most of the revenue of Mozilla Corporation comes from Google (81% in 2022[2]) in exchange of making it the default search engine in Firefox.

Source: wikipedia

Other issues I have with Firefox is the telemetry bits, the way they handle some of their employees (laying one guy off because he has cancer), the lack of meaningful updates and features in the last decade, CEO granting herself a nice pay rise after doing well nothing really. The list goes on and on honestly.

Don't get me wrong, you should still use Firefox or a Firefox derived browser if you care about a free internet. I myself use firefox (although I just switched to Zen browser on my PC which is based on Firefox). However we shouldn't be blind ourselves just because we hate anything google based and/or closed sourced. Firefox is still back by a for profit company which is, as I quoted earlier, backed at least by 80% by google.

For the positive side now it seems that in the last 2-3 months firefox has been pumping out meaningful updates (even on mobile). Things seem to be taking a positive turn recently and I'm actually a bit excited to see where firefox is going to go from here.

The Mozilla Corporation is a for profit entity owned by the non-profit Mozilla Foundation, which lets them claim to be a nonprofit, which is a sketchy looking way to set up and promote your business if nothing else. They get most of their money from Google and they've been riding AI like all the other unethical companies.

I see absolutely no reason to give them a chance, either. Just use an actual open source build instead of the mainstream one.