Firefox only (Windows/Mac/Linux): The Tabhunter Firefox extension adds quick keyboard-based tab switching to Firefox—sort of like Launchy for Firefox tabs. Just invoke Tabhunter, start typing, and Tabhunter searches for a match through all your tabs.

Everybody knows what Google is, and I can bet every Firefox’s user has used it once. If you are an obsessive Google’s user and want to add new features to it, today is your luck day. GooglePreview is a Firefox extension that inserts preview images into your Google or Yahoo search results, as well as sites’ popularity rank bar.

As the subject says, Firebug 1.3.0 Final is now up on addons.mozilla.org. Release notes are here. As mentioned previously, this version will not be compatible with Firefox 3.1 (Shiretoko) and up. For that you’ll need a Firebug 1.4 alpha, soon to be dubbed beta available on getfirebug.com’s releases directory. Notes are on the releases page.