It's not really a "switch" type of decision for me. That implies friction or commitment. I have every major browser installed, like a bowl of different flavored jelly beans. I pick whichever I want that day. Firefox isn't my favorite. A bit lower framerate rendering, a few missing features, a bit less extensions that I like. There's currently zero advantages I know of that would compel me to ever open firefox. They could literally release any novel feature that could win me over - I have no loyalty - they just don't have anything special.