Out of all the browsers I like that Mozilla were the first to point the finger to the elephant in the room while Microsoft, Google, Opera just turned a blind eye on privacy, although I don't think anyone expects much from Google these days.
Firefox has once again became my default browser on all my devices after like 6-8 years since I last used it. I guess as far as privacy concerns goes, if you are looking for a company/browser that will continue working on protecting you from trackers by default that'd be Mozilla.
Random observations that doesn't necessarily have anything to do with the topic: Firefox for windows is perfect. I actually think it's faster on Windows than on OSX for whatever reason. Playing videos, like using Netflix or Youtube is extremely sluggish on Firefox OSX, but is fine on Windows. I always end up using Safari if I want to watch a video on a higher resolution because the performance drags a lot on Firefox, especially it Netflix's overlay UI you can literally observe it's lagging behind but not in Safari.