Web Development

Most Popular See all »

  • Firebug

    Web Development
    Rated 5 out of 5 stars (1,648)
    Firebug integrates with Firefox to put a wealth of development tools at your fingertips while you browse. You can edit, debug, and monitor CSS, HTML, and JavaScript live in any web page...
    2,626,209 users
  • The best security you can get in a web browser!
    Allow active content to run only from sites you trust, and protect yourself against XSS and Clickjacking attacks.
    2,193,669 users
  • Adds ClickOnce support and the ability to report installed .NET versions to the web server.
    1,816,593 users
  • Ghostery

    Privacy & Security
    Rated 5 out of 5 stars (860)
    Protect your privacy. See who's tracking your web browsing and block them with Ghostery.
    1,150,883 users
  • Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.
    894,546 users
  • Flagfox

    Alerts & Updates
    Rated 5 out of 5 stars (581)
    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...
    795,226 users
  • Test Pilot

    Web Development
    Rated 4 out of 5 stars (63)
    Help us make Firefox better by joining our structured user studies! No need to download this add-on if you are running Firefox 4 beta, - you are already a part of the team!
    717,606 users
  • FireFTP

    Download Management
    Rated 4 out of 5 stars (840)
    FireFTP is a free, secure, cross-platform FTP/SFTP client for Mozilla Firefox which provides easy and intuitive access to FTP/SFTP servers.

    Check out my new project, FireSSH!
    707,677 users
  • Stylish

    Rated 4 out of 5 stars (616)
    Restyle the web with Stylish, a user styles manager. Stylish lets you easily install themes and skins for Google, Facebook, YouTube, Orkut, and many, many other sites. You can even customize Firefox and other programs themselves.
    689,223 users
  • Web Developer

    Web Development
    Rated 5 out of 5 stars (183)
    The Web Developer extension adds various web developer tools to the browser.
    687,408 users
  • 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.
    650,214 users
  • Remove or manage a new and uncommon kind of cookies, better known as LSO's.The BetterPrivacy safeguard offers various ways to handle Flash-cookies set by Google, YouTube, Ebay and others...

    Latest updates: See bottom link 'version history'!
    604,967 users
  • The User Agent Switcher extension adds a menu and a toolbar button to switch the user agent of a browser.
    421,730 users
  • IE Tab

    Rated 4 out of 5 stars (1,183)
    IE Tab - an extension from Taiwan, features: Embedding Internet Explorer in tabs of Mozilla/Firefox...
    396,397 users
  • FoxyProxy is an advanced proxy management tool that completely replaces Firefox's limited proxying capabilities. For a simpler tool and less advanced configuration options, please use FoxyProxy Basic.
    370,999 users
  • ColorZilla

    Web Development
    Rated 5 out of 5 stars (283)
    Advanced Eyedropper, Color Picker, Gradient Generator and other colorful goodies...
    318,658 users
  • Allows you to quickly switch to a different language (User Interface, Spell Checker Dictionary and Website content) in your Mozilla application.
    310,113 users
  • Automate Firefox. Record and replay repetitious work. If you love the Firefox web browser, but are tired of repetitive tasks like visiting the same sites every days, filling out forms, and remembering passwords, then iMacros for Firefox is the soluti...
    290,531 users

Top Rated See all »

  • Gives you a place to put all your add-on buttons without over-crowding the navigation bar.
    85,921 users
  • '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 on Windows.

    Beta builds on versions page!
    40,101 users
  • Does everything for an HTML table: Copy (table/row/column/cell), Sort (multi-column), Search (regex, range operations ...), Filter, Chart, Statistics, Rearrange, Combine/Compare. To use: Right click in a real HTML table for the "tabletools2" option.
    18,174 users
  • Inspect the DOM at lightning speed.
    20,000 users
  • CoLT

    Web Development
    Rated 5 out of 5 stars (75)
    CoLT (short for "Copy Link Text") makes it easy to copy either a link's text, or both the link text and its URL in a format you specify. This non-invasive extension simply appears as context menu items when you right-click a link. Fully customizable!
    6,554 users
  • The "NewScrollbars"-extension replaces the default scrollbars of Firefox and Thunderbird with colorized ones (partly) known from "Noia themes".
    12,438 users
  • Embed a server in your browser!
    This addon is a substitute to "POW Webserver". It lets you entertain files on your computer and let others surf to them.
    1,341 users
  • Color tools for web development.

    Color picker and eyedropper + saving colors and trying out colors with drag and drop.
    45,481 users
  • Mason

    Web Development
    Rated 5 out of 5 stars (60)
    This extension can simplify the rule to just specify the URI and Content type and can enable/disable each rule separately.
    What's more, it can customize the web pages by user scripts which is similar to Grease Monkey.
    10,344 users
  • Stylish Sync

    Rated 5 out of 5 stars (17)
    Sync engine for Stylish with backup / restore facility.
    6,026 users
  • QuickJava

    Privacy & Security
    Rated 5 out of 5 stars (204)
    Allows quick enable and disable of Java, Javascript, Cookies, Image Animations, Flash, Silverlight, Images, Stylesheets and Proxy from the Toolbar. This is great for increasing security or decreasing bandwidth.
    272,270 users
  • Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.
    894,546 users
  • Console²

    Web Development
    Rated 5 out of 5 stars (45)
    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.
    15,877 users
  • Manage form history entries (search, edit, cleanup, export/import) and easy text formfiller.

    Auto-save text entered in any form while typing to allow fast recovery when disaster strikes.

    Control for which webpage form history is saved or not.
    31,865 users
  • Firepicker

    Web Development
    Rated 5 out of 5 stars (48)
    Simple color picker plugin for Firebug.
    23,615 users
  • Exports all cookies in IE manner.
    Makes a Netscape standard cookies.txt file.
    Very useful for WGET --load-cookies option.
    8,356 users
  • Allows the use of various browser profiles (not just the user agent), which it can automatically switch to at random after a chosen period of time has expired. Supports other privacy enhancing options
    7,668 users
  • Screengrab! saves webpages as images.
    0.97 released!
    New features: upload to internet
    120,579 users

Recently Added See all »

See all 1638 extensions in Web Development »