Essential Firefox Extensions

UPDATE 4: PayPerPost says “Just kidding.”

UPDATE 3: Performancing for Firefox has been acquired by PayPerPost.com and is now known as Scribefire

UPDATE 2: I updated this post to add some new (to me) extensions, note some that are incompatible with Firefox 2.0.x and to alphabetize the list.

UPDATE: Macworld has a list of Firefox extensions for geeks. [Via etc.]

I love Firefox with a burning passion, in no small part due to its amazing repository of extensions.

You can find Firefox extensions that do all sorts of useful things from streamlining the post-to-del.icio.us process to retrieving weather forecasts, to controlling iTunes. But a few have crossed into the realm of essential.

Below is my list of which Firefox extensions you need to have, and why.

I will update this list as I find more plug-ins that I find I can’t live without. Feel free to share your essential Firefox extensions in the comments.

AdBlock

Block images and iframes from disrupting your surfing experience by blocking particular URLs.  You can block everything, for example, that comes from DoubleClick. It won’t work with Flash ads, though. For those, try Flashblock.

ColorZilla

Works similarly to the eyedropper tool in Photoshop. Pick a color from anywhere on the page and copy its Hex or RGB codes to the clipboard for use in another program. Also allows you to select colors from a palette. (Sometimes works with Firefox for Mac. Sometimes doesn’t.)

Flashblock

Block annoying Flash animations and ads with this plug-in (you just have to click first to play them). You can also white-list sites.

FireBug

DOM and JavaScript exploration and debugging with a slicker, easier-to-understand interface than some other debugging tools.

foXpose

foXpose, as its name suggests, mimics the Mac OS X Exposé feature. With one click, view all of your tabs in one screen.

IE Tab

See what a page will look like in Internet Explorer without actually firing up IE. Switch rendering engines with a single click.

LiveHTTPHeaders

Reveals invaluable information about your browser’s request and the server’s responses. Great for web application debugging.

MeasureIt

Similar to the free Rula utility for Mac OS X, MeasureIt lets you find the dimensions of a particular item on a web page.

NoScript

Have a more secure browsing experience by white-listing which sites you will allow to run JavaScript and Java applets.

Performancing

An ass-kickingly good way to post to your blog from your browser. (Read my review.)

SessionSaver 0.2.1.031

Restore your browser as you left it — either at every startup, or only after browser crashes. (Incompatible and unnecessary with Firefox 2. Plus Firefox 2 now has a crash recovery feature.)

StumbleUpon

The perfect way to waste time or find blog fodder. StumbleUpon makes web surfing cool again.

Stylish

Create and manage customized user style sheets to control the appearance of particular sites, particular pages, or for all sites you visit.

Web Developer Extension

Chris Pederick creates an extension that will validate your HTML, disable JavaScript, CSS, or images with a couple of clicks, and make your web development and testing that much easier.