Firefox is a web developer’s best friend. There are a lot of extensions which helps a web developer be more productive. Here is a list of extensions I found interesting.
Web Developer: To describe what this does will take a complete blog post. I can validate any part of a webpage, change any part of a webpage, disable anything… A must for a web developer.
IE Tab: Check out how the page looks like in Internet Explorer. I opens up the page in the current tab itself.
OperaView: Opens the page in Opera. Would be great if we had Opera Tab like the one above.
Yellowpipe Lynx Viewer Tool: Lets you see how you page would look like in Lynx, the text based browser.
Window Resizer: Resize Firefox window to see how the page looks in various resolutions.
MeasureIt: This gives you a on screen ruler to measure distances on the web page.
ColorZilla: Gives you a color picker to find out what color is used in a web page.
FireFTP: Gives a full blown FTP client to upload your web sites.
Screen Grab: Uses Java to automatically scroll through the webpage and get a screenshot of the complete page.
Remove Cookie(s) for Site: Removes the cookies of the current site.
Mozilla Accessibility Extension: Check the accessibility of your web page.
MetaTags Sidebar: Check the meta tags in your page.
LinkChecker: Check if all the links in your page are valid.
LiveHTTPHeaders: Check out what transpires between your browser and server behind the scenes.