Extension Developer's Toolbox

by Mike Kaply

9 Add-ons in this Collection

SQLite Manager by lazierthanthou

Rated 5 out of 5 stars 30 reviews

205,968 users

Manage any SQLite database on your computer.

ColorZilla by Alex Sirota

Rated 5 out of 5 stars 300 reviews

279,364 users

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

Live HTTP Headers by Daniel Savard, Nikolas Co

Rated 4 out of 5 stars 154 reviews

188,922 users

View HTTP headers of a page and while browsing.

MeasureIt by Kevin Freitas

Rated 4 out of 5 stars 327 reviews

160,160 users

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

Quick Locale Switcher by ppclick

Rated 3 out of 5 stars 81 reviews

231,856 users

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

JavaScript Debugger by James Ross, Robert Ginda, others

Rated 4 out of 5 stars 48 reviews

162,366 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.

DOM Inspector by SeaMonkey Council

Rated 5 out of 5 stars 60 reviews

146,342 users

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.

Developer Assistant by Ted Mielczarek, Gavin Sharp, others

Rated 4 out of 5 stars 46 reviews

3,390 users

A suite of tools for developers.

XUL Gear by Ilya Kharlamov

Rated 5 out of 5 stars 13 reviews

990 users

IDE for FireFox plug-in developers and business analysts who create User Interface mock-ups. A WYSIWYG XUL editor

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