With the release of Firefox version 4 last week, we thought it’s time for a fresh list of most powerful Firefox extensions for web developers. Even though couple of our mentions are not yet compatible with this latest release, we’re convinced they’ll be available in no time.
While release 4 also includes some HTML 5 enhancements, we like to see some new extensions to help developers with canvas, forms, local storage and other new features in the future.
In case, we mean just in case you don’t have Firefox yet, you can get it here.
FireBug
Javascript debugger, live DOM & CSS inspector and so much more. The de-facto single greatest web developer add-on for Firefox.
Web Developer Toolbar
Another great developer tool and addition to FireBug, adds a toolbar with powerful web developer tools at your fingertips.
Live HTTP Headers
As you browse, view live HTTP headers of any page loading in real time.
ColorZilla
An advanced eyedropper, color picker, page zoomer and various colorful goodies.
Cache Status
Easily check cache status and management from the status bar.
Edit Cookies
Edit browser cookies inside Firefox. (As of this writing, not yet compatible with Firefox 4)
Fasterfox
Test, record and improve performance and network tweaks for Firefox.
RefSpoof
Allows for easy spoofing of the HTTP referrer header.
Regular Expressions Tester
Great testing tool for regular expressions validation with colour highlighting.
User Agent Switcher
Adds a menu and toolbar button to easily switch the user agent of the browser.
Show MyIP
Simple but useful, display your current external IP address.