Firefox w/ VimFx, TreeStyleTab, Lazarus and obvious security-centric add-ons. Also, soon-to-be-self-hosted Firefox Sync. And can't forget personal user.js config file.
The situation around web browsers is just sad. Anything Chromium-based is broken by design, Mozilla only keeps on copying that, Opera recently got completely ****ed up, and MSIE should have never existed. Add to the equation mentally-challenged web devs with the same mindset as in the early MSIE vs. Netscape era... and the hell is complete.