Everyone else might be writing articles about the top 10 or 50 Firefox extensions you must have, but this is about uninstalling some extensions so your Firefox can run a little faster and use less memory.
Do you really need the Delicious extension installed on every browser you use, or can you get by with the Delicious bookmarklets? Chances are the computer you use at home and work (and possibly any other installations or virtual machines) have many of the same extensions, but you probably only need the Delicious extension on your main machine. You really should use the bookmarklets if you have Firefox set to clear “Offline Website Data” when Firefox is closed, because that will wipe out any data it synced from Delicious.
Use the program Faststone Capture instead of the Colorzilla or Fireshot extensions. Faststone Capture will let you grab color from not only your browser but anywhere on your computer. It will also take screenshots from anywhere on your computer, including your browser and it will scroll down to grab the full page. It also has a magnifier tool you can use also. However, the last freeware version is 5.3.
There are bookmarklets to send the URL you are on to other browsers, so you can eliminate the IE View or IE View Lite as well as OperaView, Safari View Win (or for OS X), Chrome View or Browser View Plus extensions.
Also, its a good idea to get to know the Web Developer extension a lot more. I’ve seen so many extensions out there that do 1 simple thing such as showing a ruler.
There are plenty of great bookmarklets out there that you can execute from your toolbar very easily and customize the placement as well. The only thing I miss is not being able to make a cool icon for bookmarklets very easily, although I know there is an extension to do it. 😀