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 easy way to download and convert Web videos from hundreds of YouTube-like sites.
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.
Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.
Never be annoyed by a Flash animation again! Blocks Flash so it won't get in your way, but if you want to see it, just click on...
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.
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!
The most beautiful yet the simplest add-on that makes a strong colorful appeal. Colors every tab in a different color and makes them easy to distinguish while beautifying the overall appearance of the interface. For Seamonkey & Flock. An essential. F...
AiOS lets you open various windows as sidebar panels, and quickly switch between them. So it put an end to the window chaos! In addition to bookmarks and history it opens dialogues such as downloads, add-ons and more in the sidebar.
Japanese to English/German/French/Russian dictionary. Just hover the mouse on top of a word, and a popup appears. Automatically de-inflects verbs and adjectives. Detailed kanji view...
Automatically inserts furigana for words written in kanji. Furigana are small characters written in kana or romaji which appear above a word.