Web Development


IE Tab Requires Restart

IE Tab - an extension from Taiwan, features: Embedding Internet Explorer in tabs of Mozilla/Firefox...

Rated 4 out of 5 stars (1,204)
180,537 users

Quick Locale Switcher Requires Restart

Allows you to quickly switch to a different language (User Interface, Spell Checker Dictionary and Website content) in your Mozilla application.

Rated 3 out of 5 stars (88)
168,577 users

RESTClient, a debugger for RESTful web services. Requires Restart

Notice: some important features (XML indentation and load old saved requests) are missing in version 2.0.0, please update to version 2.0.1.

Please follow the link ("View other versions") below To install version 2.0.1.

Rated 4 out of 5 stars (102)
147,322 users

McAfee Security Scan Plus detection

This extension allows Adobe installers to detect McAfee Security Scan Plus software is installed on your PC.

Rated 1 out of 5 stars (13)
141,727 users

Image Zoom Requires Restart

Adds zoom and rotation functionality for images...

Rated 4 out of 5 stars (346)
139,221 users

Live HTTP Headers Requires Restart

View HTTP headers of a page and while browsing.

Rated 4 out of 5 stars (170)
138,335 users

MeasureIt Requires Restart

Draw a ruler across any webpage to check the width, height, or alignment of page elements in pixels.

Rated 4 out of 5 stars (358)
130,588 users

Nimbus Screen Capture - editable screenshots Featured

1) Screen capture web pages.
2) Selected regions.
3) Whole browser windows.
Edit screenshots and save the images to either local file or Google Drive. Annotate screenshots in a very user-friendly interface with different tools. Upload and share!

Rated 5 out of 5 stars (298)
129,758 users

Screengrab (fix version) Requires Restart Featured

Screengrab! saves webpages as images.
0.99 released!
New features: upload to internet

Rated 5 out of 5 stars (306)
129,730 users

Text Link Requires Restart

Allows URI texts written in webpages to be loaded by double clicks.

Rated 4 out of 5 stars (298)
125,630 users

Modify Headers Requires Restart

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.

Rated 4 out of 5 stars (76)
125,269 users

Random Agent Spoofer

Rotates complete browser profiles ( from real browsers / devices ) at a user defined time interval. It includes many extra privacy enhancing options

Rated 5 out of 5 stars (133)
119,052 users

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.

Rated 5 out of 5 stars (70)
118,577 users


View JSON documents in the browser.

Rated 5 out of 5 stars (168)
109,178 users

JavaScript Debugger Requires Restart

As of Firefox 33, Venkman *no longer works*, as the APIs which it needs have been removed.

Venkman is the code name for Mozilla's JavaScript Debugger. Venkman aimed to provide a powerful JavaScript debugging environment for Mozilla based browsers.

Rated 4 out of 5 stars (49)
108,506 users

The Addon Bar (Restored)

Gives you a place to put all your add-on buttons without over-crowding the navigation bar.

Rated 5 out of 5 stars (333)
103,848 users

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.

Rated 5 out of 5 stars (68)
101,767 users

Selenium IDE Requires Restart

Selenium IDE is an integrated development environment for Selenium tests. It is implemented as a Firefox extension, and allows you to record, edit, and debug tests.

Rated 4 out of 5 stars (14)
98,285 users

User Agent Overrider

Override browser user agent string

Rated 5 out of 5 stars (57)
90,077 users

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.

Rated 4 out of 5 stars (226)
86,921 users