Since my list of WordPress plugins was so well-received, I’ve got another list to share. This time it’s my favorite Firefox extensions…

• Tab Mix Plus – saves your tabs and windows and will restore them if you quit out of your browser or it crashes, allows you to undo the closing of a tab, and lots more
• Performancing for Firefox – a blog editor for your WordPress, Movable Type, or Blogger blog that features integration with del.icio.us and Technorati, spellchecking, etc.
• All-in-One Gestures – execute commands by making certain movements with your mouse without having to use the keyboard, menus or toolbars — like going back a page, closing a tab, etc.
• User Agent Switcher – masquerade as Googlebot, Yahoo Slurp, or msnbot etc. to see if a site is doing bot detection
• Web Developer – tool for doing CSS coding, building web forms, etc.
• Google Toolbar for Firefox – Get query suggestions as you type into the search box, view PageRank scores, etc. Check out my screencast on installing, configuring and using the Google Toolbar.
• SEO-Links – hover over a link and it displays link popularity and rankings for the anchor text from Google, Yahoo and MSN Search. I’ve got a screencast on using SEO-Links too.
• Copy Plain Text – copy-and-paste from a web page into Microsoft Word so that the formatting isn’t carried over
• ChatZilla – IRC (Internet Relay Chat) client
• Sage – RSS feed reader
• ViewSourceWith – view the page’s HTML source using an external editor (WordPad, BBEdit, etc.)
• ShowIP – displays the IP address of the web server in the bottom right corner
• StumbleUpon – get recommendations of related pages to check out from friends and like–minded individuals
• Search engines for the Search Bar – add your own favorite search engines to the search box in the top right, such as: MSN Search, Wikipedia, LinkedIn, Technorati, Creative Commons, etc.

Here’s a tip that isn’t quite an extension, but over time it’s a huge time-saver. And it works in IE too.

• When you want to type in a URL into the address bar, you can leave off the the www. in front and the .com at the end, because, by hitting Ctrl Enter, the browser will automatically add the www. and the .com to the address for you!

This isn’t meant to be a comprehensive list of useful Firefox extensions. Check out the new FirefoxFacts ebook for a bigger list of recommended extensions and tips for Firefox. And if there’s an extension you feel should be added to the above list of favorites, please leave me a comment!