First, for anyone out there that’s pretty quick with vi, I’d recommend you check out the vimperator extension for FF if you haven’t already. It speeds up my sessions quite a bit.
It turns out vimperator sets the browser option browser.startup.page=3 for you every time you fire up your browser. You can see this in your vimperator’s options.js:
// start with saved session
storePreference("browser.startup.page", 3);
This ain’t my cup of tea for a few reasons and I’m not nuts about vimperator overriding what I’ve set in my about:config without asking or telling me. Anyway, you can override vimperator’s override.
In your ~/.vimperatorrc:
set! browser.startup.page=1