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!
United States English Spellchecker for Firefox, Thunderbird and SeaMonkey by Kevin Atkinson and Geoff Kuenning.
To enable, right-click in a multi-line text box, select "Languages", then "English (United States)".
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...
3D in your browser! FoxTab brings innovative 3D functionality to your Firefox.
New! Top Sites for FoxTab (aka Speed Dial).
Quick lookup in Wiktionary and Wikipedia, without the need to open a new tab.
Just right-click a word while shift / ctrl / alt is pressed.
Note from Mozilla: This add-on has been discontinued. Try Menu Icons Plus instead.
Adds icons to all menus along with some other features...