Serious question, is this too little too late? Firefox has taken a massive nosedive in the last few years, in the UK at least. My two big clients have them on less than 2% share. Just checked one, 5 years ago they had 9.55% share, today it's 1.8%. Even taking into account the growth of mobile, that's dire.
Firefox is about more than market share. A state of the art free non for profit browser makes the market much more competitive and better for the consumer. They are there to keep chrome/ other browsers honest. If chrome / google does something too corporate you don't like, there's an alternative.
Firefox is looking like Apple circa 1997. They can still recover, but they have to focus on what people want.