The easy way to download and convert Web videos from hundreds of YouTube-like sites.
The Web Developer extension adds various web developer tools to the browser.
Capture the whole page or any portion, annotate it with rectangles, circles, arrows, lines and text, blur sensitive info, one-click upload to share. And more!
View HTTP headers of a page and while browsing.
IE Tab - an extension from Taiwan, features: Embedding Internet Explorer in tabs of Mozilla/Firefox...
YSlow analyzes web pages and suggests ways to improve their performance based on a set of rules for high performance web pages.
http://yslow.org is the official open source website.
Adds a clear cache toolbar button. After installing the extension, find the clear cache button in the toolbar customization...
Pixel Perfect is a Firefox/Firebug extension that allows web developers and designers to easily overlay a web composition over top of the developed HTML.
Firecookie is an extension for Firebug that makes possible to view and manage cookies in your browser
Firecookie is part of Firebug since Firebug 1.10
Collections are groups of related add-ons that anyone can create and share.Explore Collections