Firefox can be extended to do just about anything you want, so why not have it help you with your web development and design? We've got a dozen suggestions to get you started down the road of turning Firefox into a powerful design and development tool in your arsenal.
Be sure to check our first toolbox of Firefox add-ons for developers and designers, too.
Font Finder - Highlight any text on a page, right click to click on "Font Finder" and you can get all of the styling information for that section.
Link Evaluator - Quickly check the links in a page to make they are resolving to live links. Good links show up as green, problem links will show up in red.
LiveHTTPHeaders - Adds a way to view the headers to the page info viewing area, will also let you work on new ones in real time.
OperaView - Just like the infamous IE ab, OperaView lets you view webpages as rendered by Opera without ever leaving Firefox.
Pagediff - Compare the coding of two different pages so that you can see where they differ. It may just help you figure out a tricky coding solution.
Python Sidebar for Mozilla - You can add this quick reference to your Firefox sidebar for quick reference to Python commands.
RankQuest - Toolbar that gives you rank checking abilities, will test your headers, verify your pages and a heck of a lot more.
SEOforFriefox - Adds information to your Yahoo and Google searches giving you instant knowledge of the site's standings with various ranking services for easy reference as you check out your competition.
SEOQuake - Gives you a lot of options for checking the ranking of your site to see how you place in various search engines.
Total Validator - An all-in-one validation tool that will check HTML, Links, take screenshots and a lot more.
Validaty - Adds a one-click button to check the validness of the HTML in a page.
View Cookies - Adds a tab to the Page Info screen that lets you see the cookies being set by a page, a quick way to test your own cookies.
ViewSourceWith - Allows you to open files such as CSS in external editors directly.
Web Developer Toolbar - Gives you a plethora of tools such as disabling portions of a web page, shutting off cookies, viewing source and more.
Window Resizer - Automatically resize your browser window between 640x480, 800x600, 1024x768, 1280x1024, 1600x1200 to see how pages appear at these resolutions.
