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).
Download all the links, movies and audio clips of a page at the maximum speed with a single click, using the most popular, lightweight and reliable external download managers.
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.
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...
FireShot Webpage Screenshots captures pages entirely. Demo: http://bit.ly/RlBQMV
Screenshots can be quickly captured and:
― Saved as Image or PDF
― Sent to clipboard
― Annotated *
― Uploaded *
― E-Mailed *
* OS Windows only
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!
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)".
Use tamperdata to view and modify HTTP/HTTPS headers and post parameters...
Note: If you are encountering the Connecting... problem see instructions below.
The updated, fully supported IE Tab. Embed IE in a Firefox tab. IE Tab Features: FF 4+ support, IE 7-9 compatibility modes, old IE Tab settings import.
Session Manager saves and restores the state of all or some windows - either when you want it or automatically at startup and after crashes. It can also automatically save the state of open windows individually.
Personas are free, easy-to-install "skins" for Firefox. Personas Plus extends that built-in functionality to give you even more control and easier access to new, popular, and your own favorite Personas.