Web Development


Pearl Crescent Page Saver screenshot tool Requires Restart

Save an image of a web page (including Flash content) to a file. Web page screenshots may be captured interactively or from the command line. Options allow you to control the output format (PNG or JPEG), image file name, scaling, and much more.

Rated 4 out of 5 stars (91)
100,011 users

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.

Rated 5 out of 5 stars (36)
99,392 users

HttpFox Requires Restart

An HTTP analyzer addon for Firefox

Rated 4 out of 5 stars (170)
98,403 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)
96,697 users

User Agent Overrider

Override browser user agent string

Rated 5 out of 5 stars (59)
94,838 users

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 +

Rated 3 out of 5 stars (87)
93,344 users

Emoji Cheatsheet

A reference for the codes to generate Emojis on popular sites like GitHub or Basecamp and Unicode characters for Twitter and Facebook.
Search Emojis by name or view recently selected items. Emojis are automatically copied to the clipboard.

Rated 4 out of 5 stars (29)
92,623 users


A very simple extension for learning web page colors. Copy the RGB or Hex color code of any pixel displayed in your browser to the clipboard (in CSS/HTML format). Similar in function to Internet Explorer's color picker.

Rated 4 out of 5 stars (42)
92,609 users


Wappalyzer is a browser extension that identifies software on websites.

Rated 4 out of 5 stars (103)
92,291 users

YSlow Requires Restart

YSlow analyzes web pages and suggests ways to improve their performance based on a set of rules for high performance web pages.
http://yslow.org is the official open source website.

Rated 3 out of 5 stars (215)
88,089 users

Clear Cache Button Requires Restart

Adds a clear cache toolbar button. After installing the extension, find the clear cache button in the toolbar customization...

Rated 4 out of 5 stars (134)
79,907 users

RefControl Requires Restart

Control what gets sent as the HTTP Referer on a per-site basis.

Rated 4 out of 5 stars (186)
79,161 users

IE View Requires Restart

Lets you load pages in IE with a single right-click, or mark certain sites to *always* load in IE.

Rated 3 out of 5 stars (153)
77,020 users

SeoQuake SEO extension

Accelerate your SEO efforts on the fly. SEOquake is a free plugin for browsers that provides you with key SEO metrics for a specific page, along with other useful tools such as SEO Audit and many others.

Rated 4 out of 5 stars (214)
73,940 users

Fire IE (FireIE, Enhanced IE) Requires Restart

Embeds Internet Explorer(IE) to use the powerful Firefox add-ons.
Not only an enhanced IE Tab, but also an enhanced Internet Explorer with Adblock Plus and FireGestures support.
Switch to the IE engine in one click and dismiss your IE.

Rated 4 out of 5 stars (180)
72,740 users

Custom Buttons Requires Restart

Gives a possibility to create custom toolbarbuttons...

Rated 4 out of 5 stars (113)
70,679 users

JS Print Setup Requires Restart

Client side Javascript printer settings.
This extension implements print setup from CS Javascript, similar of MeadCo's ScriptX ActiveX control for Internet Explorer.

Rated 5 out of 5 stars (25)
68,167 users

Autofill Forms Requires Restart

Autofill Forms enables you to fill out web forms with one click.

Rated 3 out of 5 stars (412)
67,968 users

User-Agent Switcher Featured

Quickly and easily switch between popular user-agent strings.

Rated 4 out of 5 stars (32)
67,134 users

CacheViewer Requires Restart

This extenion is GUI Front-end of "about:cache"...

Rated 4 out of 5 stars (225)
66,969 users