Pro Developer

by JamesWilson

37 Add-ons in this Collection

Adblock Plus by Wladimir Palant

Rated 5 out of 5 stars 4,983 reviews

21,231,998 users

Blocks annoying video ads on YouTube, Facebook ads, banners and much more.

Adblock Plus blocks all annoying ads, and supports websites by not blocking unobtrusive ads by default (configurable).

Firebug by Joe Hewitt, Jan Odvarko, others

Rated 5 out of 5 stars 1,793 reviews

2,317,059 users

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...

DownThemAll! by Nils Maier, Federico Parodi, others

Rated 5 out of 5 stars 1,614 reviews

1,365,361 users

The first and only download manager/accelerator built inside Firefox!

Greasemonkey by Anthony Lieuallen, Aaron Boodman, others

Rated 4 out of 5 stars 959 reviews

1,264,935 users

Customize the way a web page displays or behaves, by using small bits of JavaScript.

Web Developer by chrispederick

Rated 5 out of 5 stars 217 reviews

555,467 users

The Web Developer extension adds various web developer tools to the browser.

FoxyProxy Standard by Eric H. Jung, groeg, others

Rated 4 out of 5 stars 343 reviews

297,407 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.

Full Web Page Screenshots (♥♥♥♥♥) by susbox

Rated 5 out of 5 stars 438 reviews

268,579 users

FireShot makes full web page screenshots. Demo:

Screenshots can be quickly captured and:

― Saved as Image or PDF
― Sent to clipboard
― Printed
― Annotated *
― Uploaded *
― E-Mailed *

* OS Windows only

Tamper Data by Adam Judson

Rated 4 out of 5 stars 132 reviews

114,867 users

Use tamperdata to view and modify HTTP/HTTPS headers and post parameters...

ColorZilla by Alex Sirota

Rated 5 out of 5 stars 305 reviews

295,325 users

Advanced Eyedropper, Color Picker, Gradient Generator and other colorful goodies...

ReloadEvery by Jaap Haitsma

Rated 4 out of 5 stars 676 reviews

171,263 users

Reloads web pages every so many seconds or minutes. The function is accessible via the context menu (menu you get when you right click on a web page) or via tab context menu (right click on the tab)

JavaScript Debugger by James Ross, Robert Ginda, others

Rated 4 out of 5 stars 50 reviews

133,397 users

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.

Live HTTP Headers by Daniel Savard, Nikolas Co

Rated 4 out of 5 stars 157 reviews

169,043 users

View HTTP headers of a page and while browsing.

MeasureIt by Kevin Freitas

Rated 4 out of 5 stars 339 reviews

153,230 users

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

ColorfulTabs by Shivanand Sharma

Rated 4 out of 5 stars 992 reviews

225,744 users

The most beautiful yet the simplest add-on that makes a strong colorful appeal. Colors every tab in a different color and makes them easy to distinguish while beautifying the overall appearance of the interface. For Seamonkey & Flock. An essential. F...

YSlow by YSlow

Rated 3 out of 5 stars 195 reviews

101,438 users

YSlow analyzes web pages and suggests ways to improve their performance based on a set of rules for high performance web pages. is the official open source website.
  1. 1
  2. 2
  3. 3
Results 115 of 37

What are Collections?

Collections are groups of related add-ons that anyone can create and share.

Explore Collections

Recently Viewed