• Not sure if I like these

• Adblock Plus
• Add on Compatibility Reporter : This allows you to ignore version constraints on old or unmaintained add-ons
• Delicious bookmarks : I use this in “classic” mode and don’t sync my firefox bookmarks to delicious
• Download Statusbar
• Flashblock
• Keyconfig : This is vital on linux machines in order to reclaim the backspace key as a “back” button
• Lastpass
• Live HTTP Headers
• Permit Cookies : Great for setting a default of “Keep cookies until i close firefox” and then easily adding exceptions for sites you want to always have a cookie for you.
• Priv3
• Session Manager : Never loose your tabs again (due to a crash or mistake)

Not sure if I like these

• http://www.eff.org/https-everywhere
  • It just breaks so many sites and after filing a bug with the developers, detailing even the fix, there’s been no movement