ForecastFox is an interface to some popular weather sites, but you can set it to display mini icons in the status bar or the main Firefox toolbar. I prefer seeing the information in the status bar, where I can get a forecast at a glance for my chosen area. A double-click on the icon takes you directly to a more detailed forecast on weather.com.
QuickNote makes it easy to send highlighted text directly to a file, and will even append the URL of the site on which you found the text for handy reference. QuickNote will open up in a tabbed browser window, a floating window, or as a sidebar, depending on your preferences, and you can set up multiple tabs within an open note.
Chatzilla began as a separate component of the Mozilla suite. Now it's a lightweight extension that adds IRC chat to Firefox. There are also rumors of an extension that implements a client for the Jabber chat protocol, but there don't seem to be any installable files available for the general public.
Development tool extensions can be invaluable when you're designing a Web site. For example, I browsed around the extensive collection of Web templates of the Open Source Web Design community, getting instant information on HTML compliance with Checky, an interface to several online validation services, most of which are free. HTML Validator, based on the W3C's Tidy, can also be set up to display warnings and error lists in the Firefox status bar, with mini icons or text. Double-click on the icon to see the source of the current page in a window with the Validator's suggestions to clean up the page.
ViewSourceWith allows you to open the currently loaded page's source in the editor of your choice with a right-click. This is helpful for complex sites you might want to see in a more featureful editor, like Bluefish or PageMaker. You can configure it to offer a list of several editors.
For Web designers on a Windows machine, there's also ieview, which opens the current page in Internet Explorer for a quick comparison of the same page in different browsers. This saves you the distraction of copying and pasting a link into Internet Explorer.
One tip for better productivity with extensions is to use Firefox profiles. I use several different Firefox profiles, depending on which set of extensions I'm using most. For instance, I set up a Web development profile, in which the extensions I need for Web site development are loaded. To start Firefox with a specific profile, start Firefox from a command line (on Windows from the Run menu) with the
-profilemanager argument, click Create Profile, select a name, then start up with the new profile, either from the profile manager or with the command line switch
-P myprofile. Then you can install the extensions you want for a specific need, and they'll be activated only in that profile.
Our series this week highlights just a few of the useful Firefox extensions currently available. There are hundreds more to choose from, and new extensions are being developed all the time.