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).
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.
Download Flash and Video is a great download helper tool that lets you download Flash games and Flash videos (YouTube, Facebook, Dailymotion, Google Videos and more) with a single click.
The downloader is very easy to use.
Adblock Edge is a fork of the Adblock Plus version 2.1.2 extension for blocking advertisements on the web, without sponsored ads whitelist.
With this addon you can translate any text to your own language with one click or hot-key. You can either translate the selected text, this way the translated text will overwrite the original selected text, or you can translate the full page too.
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.
LastPass, an award-winning password manager, saves your passwords and gives you secure access from every computer and mobile device.
This add-on is a downloader that lets you easily download MP4 videos and MP3 music from sites like Youtube, Facebook, Metacafe, Dailymotion, Break, VKontakte and music for example from SoundCloud, Grooveshark and from many other sites...
MORE THAN 21 MILLION DOWNLOADS
ImTranslator provides translation powered by Google Translate, Microsoft, Babylon for 70+ languages. It includes Translator, Dictionary, Text-to-Speech, Back Translation.
Video Tutorial: http://youtu.be/qyLyFkQuMGU
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.
Squared tabs, appmenu, add-on bar, small button view and many more 'old' features for Firefox 29+ (Windows / MacOSX / Linux).
All builds & changelogs on versions page!
Xmarks is the #1 bookmarking and open tab add-on. Keep your bookmarks, and open tabs backed up and synchronized across computers and browsers. Mobile phones with Premium access. Utilize LastPass to sync passwords!