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 first and only download manager/accelerator built inside Firefox!
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.
The Web Developer extension adds various web developer tools to the browser.
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
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...
FEBE (Firefox Environment Backup Extension) allows you to quickly and easily backup your Firefox extensions. In fact, it goes beyond just backing up -- It will actually rebuild your extensions individually into installable .xpi files.
Signatures for Gmail, Google Mail, Yahoo Mail