Most Popular Extensions
HttpRequester Requires Restart
A tool for easily making HTTP requests (GET/PUT/POST/DELETE), viewing the responses, and keeping a history of transactions.
Zoom Page Requires Restart
Full featured zoom manager with independent page and image zoom modes. Choose from four zoom modes: Default Zoom, Fit-To-Width, Default Zoom + Site Specific or Fit-To-Width + Site Specific. Button style and zoom levels are fully configurable.
Cookies Manager+ Requires Restart
Cookies manager to view, edit and create new cookies. It also shows extra information about cookies, allows edit multiple cookies at once and backup/restore them.
As of Firefox 33, Venkman *no longer works*, as the APIs which it needs have been removed.
Lookup scholarly articles as you browse the web.
Download and save videos playing on a website like youtube to your hard disk
Tree Style Tab Requires Restart
Show tabs like a tree.
This extension automatically sets Yahoo.com as your homepage and new tab page.
Play all videos on YouTube with your preferred settings (size, quality, playback rate, …) without cookies using only HTML5.
UnMHT allows you to view MHT (MHTML) web archive format files, and save complete web pages, including text and graphics, into a single MHT file in Firefox/SeaMonkey.
ipFood Requires Restart Featured
Simulate the use of a series of proxy changing at each new connection.
Fast Dial Requires Restart
Visual bookmarks for Firefox.
Access your Identity Safe Vault, which remembers your usernames and passwords for single-click access to your favorite sites.
Manages the Remote XUL whitelist to allow websites and local files to load XUL content. For versions compatible with Firefox 41 and lower, see All Versions page below.
Unblock any blocked website or content and stay secure and private with Hotspot Shield VPN. Easy-to-use interface with one-click activation. Unlimited bandwidth, completely FREE!
ChatZilla Requires Restart
A clean, easy to use and highly extensible Internet Relay Chat (IRC) client.
Gives you a place to put all your add-on buttons without over-crowding the navigation bar.
A very simple extension for learning web page colors. Copy the RGB or Hex color code of any pixel displayed in your browser to the clipboard (in CSS/HTML format). Similar in function to Internet Explorer's color picker.
NoSquint Requires Restart
NoSquint is no longer maintained. :(
By blocking annoying ads and nosy trackers, adaware ad block nearly doubles your browsing speed! And with the most robust antivirus-level cloud-scanning technology of any ad blocker on the market, you’ll be safe from the latest cyber-threats.