What it would take to replace Firefox as my web browser
In the wake of Firefox's decision to support EME (cf) a number of people have been angrily advocating for switching away from Firefox to another browser. I think that this is wrong-headed (see here (via) for one cogent explanation of why), but let's set that aside for now and merely ask what it would take for something to replace Firefox as my web browser.
At one level the answer can be garnered from the Firefox extensions that I use. I don't just want 'a web browser'; I want a web browser with gestures and some equivalent of NoScript (practically speaking I also want the ability to edit text areas in a real editor). I also need a browser that can be remote controlled to open new URLs in new windows, because this is a big part of how I use Firefox in practice, but I think basically all of them will do that these days.
But that isn't the full story. What I really require is a browser and a set of extensions that I can trust both now and in the future, and this is at least partly a cultural issue that goes deep. As I've found out the hard way, Chrome does not have the right culture; 'good' Chrome extensions that provided more or less the equivalent of my Firefox environment have gone bad. It's likely that any smaller open source browser would have a browser and extensions culture that was good, but it's not absolutely guaranteed, and I don't think that I can really trust a commercial browser these days (sorry, Opera, although I may be selling you short).
All of which brings me around to my strong impression that there are no real browser alternatives left. In some ways Unix users have it better than Windows and Mac users, in other ways worse; we lack highly capable native system browsers but we have a number of reasonably capable free alternatives not beholden to various commercial interests, alternatives that optimistically might develop into something reasonably capable.
(If I were serious about evaluating Firefox alternatives I think I'd have to look at Konqueror (although it seems to lack a NoScript equivalent) and Opera. Gnome has a browser but I doubt it's going to appeal to a power user like me. There are other Unix browsers but my impression is that none of them are up to a competitive level.)