Web Development

Most Popular See all »

  • Firebug

    Web Development
    Rated 5 out of 5 stars (1,770)
    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...
    2,363,090 users
  • Adds ClickOnce support and the ability to report installed .NET versions to the web server.
    2,298,587 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.
    2,132,578 users
  • Ghostery

    Privacy & Security
    Rated 5 out of 5 stars (1,155)
    Protect your privacy. See who's tracking your web browsing and block them with Ghostery.
    1,421,180 users
  • Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.
    761,587 users
  • Test Pilot

    Web Development
    Rated 4 out of 5 stars (71)
    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!
    756,086 users
  • Stylish

    Appearance
    Rated 4 out of 5 stars (738)
    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.
    708,321 users
  • Flagfox

    Alerts & Updates
    Rated 5 out of 5 stars (632)
    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...
    625,891 users
  • Web Developer

    Web Development
    Rated 5 out of 5 stars (213)
    The Web Developer extension adds various web developer tools to the browser.
    574,377 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'!
    566,207 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.
    560,968 users
  • FireFTP

    Download Management
    Rated 4 out of 5 stars (924)
    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!
    560,040 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...
    481,901 users
  • The User Agent Switcher extension adds a menu and a toolbar button to switch the user agent of a browser.
    382,994 users
  • Add, modify and filter the HTTP request headers sent to web servers. This addon is particularly useful for Mobile web development, HTTP testing and privacy.
    314,314 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.
    312,109 users
  • IE Tab

    Tabs
    Rated 4 out of 5 stars (1,185)
    IE Tab - an extension from Taiwan, features: Embedding Internet Explorer in tabs of Mozilla/Firefox...
    273,385 users
  • 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
    ― Printed
    ― Annotated *
    ― Uploaded *
    ― E-Mailed *

    * OS Windows only
    266,520 users

Top Rated See all »

  • 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.
    17,455 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!
    40,152 users
  • Open With Photoshop

    Appearance
    Rated 5 out of 5 stars (43)
    Open With Photoshop is a new companion for web and graphic designers to open up any web image with Adobe Photoshop via a single and quick mouse click.
    14,232 users
  • Gives you a place to put all your add-on buttons without over-crowding the navigation bar.
    129,688 users
  • Stylish Sync

    Appearance
    Rated 5 out of 5 stars (19)
    Sync engine for Stylish with backup / restore facility.
    5,739 users
  • Inspect the DOM at lightning speed.
    15,801 users
  • The "NewScrollbars"-extension replaces the default scrollbars of Firefox and Thunderbird with colorized ones (partly) known from "Noia themes".

    Firefox 32 zoom bug with custom scrollbars got fixed in Firefox 33 beta 6, Aurora and Nightly!
    15,149 users
  • cliget

    Download Management
    Rated 5 out of 5 stars (45)
    Download files using curl or wget. This addon generates curl/wget commands that emulate the request as though it's coming from your browser allowing you to download protected files directly to a separate machine (e.g. server).
    6,137 users
  • Mason

    Web Development
    Rated 5 out of 5 stars (64)
    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.
    7,759 users
  • Color tools for web development.

    Color picker and eyedropper + saving colors and trying out colors with drag and drop.
    36,847 users
  • QuickJava

    Privacy & Security
    Rated 5 out of 5 stars (248)
    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.
    261,801 users
  • Console²

    Web Development
    Rated 5 out of 5 stars (47)
    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.
    10,432 users
  • Rotates complete browser profiles ( from real browsers / devices ) at a user defined time interval. It includes many extra privacy enhancing options
    27,926 users
  • Domain Auction Metrics by DomCop provides domain metrics for GoDaddy Auctions, NameJet, SnapNames, DynaDot and Sedo. View Page Rank, Majestic Trust Flow, Moz Rank and Domain Authority, SimilarWeb Rank, SEMrush Metrics, Alexa Rank, Estibot metrics.
    1,262 users
  • Open Dom Inspector at this node from Inspect on context menu. Dom Inspector must already be installed. Handy for checking both page for web developers and chrome for extension...
    1,589 users
  • Screen capture Web Page, selected region or whole browser window, edit screenshots and save the images to Local File or Google Drive. Edit screenshots in a very user-friendly interface with the different tools.
    98,148 users
  • This addon predicts your character based on date of birth
    This add on would be added to addon bar above the taskbar with name HCGdora and click on it to open
    96 users
  • Easy and convenient screenshot tool. Allows you to make screenshots of any selected area (video and flash too), edit and upload it to server.
    50,302 users

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See all 1848 extensions in Web Development »