Web and Developer Tools
Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.
User Agent Switcher Requires Restart
The User Agent Switcher extension adds a menu and a toolbar button to switch the user agent of a browser.
SQLite Manager Requires Restart
Manage any SQLite database on your computer.
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.
Live HTTP Headers Requires Restart
View HTTP headers of a page and while browsing.
As of Firefox 33, Venkman *no longer works*, as the APIs which it needs have been removed.
Proxy Tool Requires Restart
Proxy Tool - Powerful, yet User-friendly proxy tool to manage your proxies and anonymity needs, including: 46M+ user agents (world's largest), 10 different spoofed HTTP referrers, auto-proxy rotation, plus many more. Developed by http://ProxyList.co
DOM Inspector Requires Restart
DOM Inspector is a tool that can be used to inspect and edit the live DOM of any web document or XUL application. The DOM can be navigated using a two-paned window displaying a variety of different views on the document and all nodes within.
RefControl Requires Restart
Control what gets sent as the HTTP Referer on a per-site basis.
HttpFox Requires Restart
An HTTP analyzer addon for Firefox
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 +
'Classic Toolbar Buttons' add-on restores old toolbar button ui (known from Fx 4-7s small view, Fx 4-12s large view & Tb 5-14) for current Firefox, Thunderbird and Seamonkey versions.
Beta builds on versions page!
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.
Scriptish Requires Restart
The greatest user script engine on the Internet (a fork of Greasemonkey).
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.
WorldIP - Geo Add-on with Security Features Requires Restart
Professional Geo Add-on with security features and advanced network tools. Anti-phishing. Protection against DNS spoofing and fake sites. All DNS records for domain. The real location of web server, country flag, extended information about datacenter
Firesizer Requires Restart
Allows you to resize the window to specific dimensions.
NOTE: Users of Firefox 29 and above must install "The Addon Bar" extension to use this, as Firesizer uses the add-on bar that has been removed in Firefox 29.
Dafizilla Table2Clipboard Requires Restart
Mozilla applications allow to select rows and columns from a table simply pressing Control key and picking rows/columns with left mouse button.
The selection can be copied to clipboard but the original table disposition is lost making ugly results wh...
Linkification Requires Restart
Converts text links into genuine, clickable links...