Here’s a list of my recommended firefox extensions:
- Adblock Plus - Blocks adverts and other annoying things, includes auto-updating block lists.
- British English Dictionary - Required for us Brits for the inbuilt spell checker in firefox 2.x
- Fasterfox - Tweaks the firefox network settings to get a bit more performance out of firefox
- Firebug - New debug console for firefox, shows errors with pages, and lots of other useful debug stuff, like network times, dom inspector (you can even edit attributes in pages)
- Forecasfox Enhanced - Shows the weather in your status bar
- IE Tab - Enables IE within a tab
- Tab Mix Plus - Customisation of how tabs and windows work
All these can be got from the above links or https://addons.mozilla.org/.
Firebug on the mozilla site is the old stable version, get the beta from the link above it’s a massive improvement with a load more features.