I switched back to Firefox 54 from Chrome when multiprocess browsing ("Electrolysis") came out of beta. It's been absolutely great. It's fast and I trust and like the nonprofit behind it. And all the extensions I care about are available.

My main issue with Chrome was the endless nags to sign in to a Google account, and just generally wanting less dependence on Google. I also like that Firefox has a built in tracking protection (not just Do Not Track toggle but actual blocking of trackers). That's something that's just not in Google's interest to put in Chrome.

Browsers are becoming more and more aggressive in protecting the interests of users. Becoming true "User Agents," in other words. See also Safari iOS allowing content blockers and now in iOS 11 blocking some popular tracking behaviors by default. It's absolutely great. And it's not surprising to me that Chrome is not a leader here. It's owned by the biggest advertising company on the internet. I predict Chrome will continue to lag on pro-privacy, anti-nag features.