Let's not overstate things. Firefox 57 gained good will from some users. It also seriously annoyed others, both because of the loss of many useful extensions, and because the new version is horribly buggy and crashes all the time.
The one thing Mozilla still had going for them compared to Google or Microsoft was the emphasis on privacy and respecting the user, and yet I've read about several different cases in recent weeks where that trust has been undermined, this being the latest.