I installed a browser extension to see what it does and how (someone wanted to promote it for a place I moderate so I thought I’d check it out) and once done I uninstalled it. Then I checked about:config and found a trace of it left so I thought I’d do a completely fresh install of Firefox. It’s surprising maybe just how much customisation I’d done.
Tab Mix Plus – lets you export your settings.
Flashblock – I forgot to note my exceptions
Adblock Plus – I forgot to note my exceptions again
Search Engines – I forgot to note those I have added
Greasemonkey – I forgot to note the scripts I use
Reddit Enhancement Suite – I forgot to back this up. Lost all my user tagging which is a huge PITA.
Firefox Privacy Settings – cannot export any prefs at all
Firefox Proxy – it installs to use the System Proxy, not No Proxy. (why?)
Hopefully now I’ve written this the next time I do this I’ll remember.