Blocks annoying video ads on YouTube, Facebook ads, banners and much more.
Adblock Plus blocks all annoying ads, and supports websites by not blocking unobtrusive ads by default (configurable).
Flash Video Downloader helps you to download any video (flv, mp4, HD) from YouTube-like, Facebook, Break, Metacafe and more in one click. You can download mp3, music (iPod), avi and more. Download Flash games. Download Helper.
The best security you can get in a web browser!
Allow active content to run only from sites you trust, and protect yourself against XSS and Clickjacking attacks.
Protect your privacy. See who's tracking your web browsing and block them with Ghostery.
Restyle the web with Stylish, a user styles manager. Stylish lets you easily install themes and skins for Google, Facebook, YouTube, Orkut, and many, many other sites. You can even customize Firefox and other programs themselves.
Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.
YouTube High Definition is a powerful tool that will let you play all YouTube videos in High Definition automatically.
Displays a country flag depicting the location of the current website's server and provides a multitude of tools such as site safety checks, whois, translation, similar sites, validation, URL shortening, and more...
Tab Mix Plus enhances Firefox's tab browsing capabilities. It includes such features as duplicating tabs, controlling tab focus, tab clicking options, undo closed tabs and windows, plus much more. It also includes a full-featured session manager.
The Web Developer extension adds various web developer tools to the browser.
With EPUBReader you can read ePub files just in Firefox. No additional software needed!
The most lightweight and easiest translator. Translate between more than 50 languages with one click or a hot key. Translate from one word to a whole page.