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Choose from thousands of extra features and styles to make Firefox your own.
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Restartless Restart
This 15KB restartless add-on will add a "File" -> "Restart" menu item and a ctrl/cmd + alt + r hotkey to restart Firefox or Seamonkey.
Remote XUL Manager
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.
Scriptish Requires Restart
The greatest user script engine on the Internet (a fork of Greasemonkey).
IE Tab + (FF 8+, 7, 6, 5, 4, 3.6, 3.5, SeaMonkey) Requires Restart
IE Tab + is an enhanced version of IE Tab. It supports FF 3.5 or greater, integrates IE Tab with Adblock Plus in the IE Tab engine, and synchronizes cookies between IE and Firefox. You can easily import settings from the original IE Tab into IE Tab +
Launchy Requires Restart
Launchy will enable you to open links and mailto's with external applications...
RequestPolicy Requires Restart
Be in control of which cross-site requests are allowed. Improve the privacy of your browsing by not letting other sites know your browsing habits. Secure yourself from Cross-Site Request Forgery (CSRF) and other attacks.
Copy Pure Text Requires Restart
Allows to copy selected text as plain text by adding a 'Copy as Text' menu item to context menu.
Config Descriptions
Shows source comments for advanced application preferences in about:config
Leet Key Requires Restart
Transforms typed or static text to L337, ROT13, BASE64, HEX, URL, BIN, DES, AES, Morse code, DVORAK keyboard layout and to lower/to upper case functionality, Leet Font...
Console² Requires Restart
Console² (pronounced Console Squared or Console Two) replaces the JavaScript Console with what could be the next generation Error Console. From v0.5 includes the Console Filter extension previously available separately from the Console² website.
Colorific
Colorize entire web pages. Configure themes using sliders and drag-and-drop. Set domain preferences for automatic coloration.
Whois Lookup & Hosting & DNS & Site Flags Firefox Requires Restart
IP Whois Lookup & Website Reviews & Rating. Display country flag indicating website location. Alexa and Norton Antivirus Site Adviser. Supported: GoDaddy, NetworkSolutions, Dotster, 1and1, NameCheap, Register, Yahoo, 123-Reg, FatCow, Enom, FastHosts.
Font Finder Requires Restart
FontFinder is created for designers, developers and typographers. It allows a user to analyze the font information of any element on a page, copy any piece(s) of that information to the clipboard, and perform inline replacements to test new layouts.
NoRedirect Requires Restart
NoRedirect lets the user take control of HTTP redirects. It can be used to interdict an ISP's DNS search redirection hijacks, preview/screen "shortened" URLs (e.g., TinyURL), stop the annoying redirection of "smart" error pages, etc.
Color Transform
Transform the colors of entire web pages or selected elements. Combine predefined themes with basic transforms. Save transforms for specific web domains.
To create your own collections, you must have a Mozilla Add-ons account.