However, Australis for example was a large redesign of the UI. I'm not sure how you can support an opt-out, as that would mean supporting two codebases - two different and separate UIs, at once.
Isn't it frustrating when a major software vendor takes a product you rely on, updates the whole UI in a way that makes the product worse for you and many other people using the desktop version primarily in order to try to make it better for the tiny number of people using the mobile version, and then makes clear that if you don't go for their new version you'll also miss out on critical bug fixes and security updates for the old one within a few months?
Nope, I used Firefox LTS 24 as long as I could. But by LTS 31 (which wasn't very long), we were back to Australis.
And Firefox 24 is missing a whole lot of really critical functionality.
You really have no choice but to trust the random third-party developer of Classic Theme Restorer not to do anything malicious, and pray that he doesn't ever quit.
Sadly, I have discovered that Mozilla and I have very different ideas of what "long term" means.
The irony of my previous post is that both Microsoft and Mozilla seem to be playing the same game now, right down to sub-year "long term" support. You can't really choose whether to have those updates any more, only to defer them for a short while. Anything more than that, and you just have to give up on updating altogether, security updates included, and for a new OS that is even more dangerous than it is for a browser.
Honestly with everything becoming web apps these days, I'm starting to feel it's more dangerous for the browser than for the OS. So many zero-day exploits like the recent Microsoft OpenType bug. And of course, Flash. Enough said there.
I'm already to the point where I don't web surf on my primary development box, outside of localhost (site dev work.)
As long as your firewall seals off all unrequested external traffic (easy with pf), and you don't run untrusted desktop applications, then the only real attack vector is through your browser.
I'm not quite that strict with my main work machine, but I am very careful about what I install on it, and typically my browsing is all work related or the occasional site likely to be very safe (BBC News at lunchtime, say).
I do want to point out that the OpenType issue you mentioned is really an OS bug rather than a browser one, though. It's a good demonstration that ultimately any OS facility that is used by browsers is a potential vulnerability, and crucially it's a cross-browser vulnerability and therefore more attractive to attackers.
What I'd really like is for all my platform software -- OS, browsers, language runtimes and the like -- to focus on stability and quality, with new features taking a secondary role. But I guess that doesn't sell new and shiny to customers^Wconsumers with an Internet-era attention span. :-(
Isn't it frustrating when a major software vendor takes a product you rely on, updates the whole UI in a way that makes the product worse for you and many other people using the desktop version primarily in order to try to make it better for the tiny number of people using the mobile version, and then makes clear that if you don't go for their new version you'll also miss out on critical bug fixes and security updates for the old one within a few months?