Here's a quick post on how I use and configure Firefox on my Macs. The last time I posted about any of this was in 2011, and things have changed a fair bit since then. First, a screenshot (from my new iMac):

Key extensions for this setup:

Vim Vixen

Vim keybindings for Firefox. Not quite as good as Vimperator, but works with modern Firefox, and getting better all the time. The only thing I really miss is macro recording, which I used all the time in Vimperator.

Tree-Style Tabs

Our monitors are widescreen; why would you try to stack tabs …