Firefox and Chrome are the two major parties, and IE/Opera/Safari are third parties.There’s no way this can be true.
Apple owns various platforms that ship Safari/WebKit and it’s the only option on iOS and watchOS. They’ve shipped more than 2 billion (and growing) iOS devices.
And hundreds of thousands native iOS apps use WebKit views.
So there’s no way Safari is a fringe 3rd party browser and has a better privacy story regarding fingerprinting and tracking than any of the other major browsers, including Firefox.
Unless you’re on the W3C mailing lists and GitHub repos, you wouldn’t know how active the WebKit team is on the development and implementation of web standards.