mastergenius web developer addons

by mastergenius

19 Add-ons in this Collection

Firebug by Joe Hewitt, Jan Odvarko, others

Rated 5 out of 5 stars 1,801 reviews

2,704,207 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...

Greasemonkey by Anthony Lieuallen, Aaron Boodman, others

Rated 4 out of 5 stars 964 reviews

1,363,522 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 218 reviews

638,054 users

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

SQLite Manager by lazierthanthou

Rated 5 out of 5 stars 41 reviews

230,659 users

Manage any SQLite database on your computer.

Flagfox by Dave G

Rated 5 out of 5 stars 636 reviews

655,173 users

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...

Tamper Data by Adam Judson

Rated 4 out of 5 stars 133 reviews

130,040 users

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

FireGestures by Gomita

Rated 4 out of 5 stars 887 reviews

404,263 users

A customizable mouse gestures extension which enables to execute various commands and user scripts with six types of gestures.

ColorZilla by Alex Sirota

Rated 5 out of 5 stars 306 reviews

339,959 users

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

JavaScript Deobfuscator by Wladimir Palant

Rated 5 out of 5 stars 19 reviews

67,781 users

This add-on shows you what JavaScript code runs on a web page, even if it is obfuscated and generated on the fly. Simply open JavaScript Deobfuscator from the Web Developer menu and watch the scripts being compiled/executed.

MeasureIt by Kevin Freitas

Rated 4 out of 5 stars 341 reviews

179,116 users

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

YSlow by YSlow

Rated 3 out of 5 stars 200 reviews

114,787 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.

Tree Style Tab by Piro (piro_or)

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Rated 4 out of 5 stars 1,256 reviews

108,311 users

Show tabs like a tree.

Html Validator by Marc Gueury

HTML Validator is a Mozilla extension that adds HTML validation inside Firefox and Mozilla. The number of errors of a HTML page is seen on the form of an icon

For Online HTML 5 validation, you need 0.962

Firefinder for Firebug by Robert Nyman

Rated 3 out of 5 stars 28 reviews

26,403 users

Finds HTML elements matching chosen CSS selector(s) or XPath expression

Extended Statusbar by Strahinja Kustudić

Rated 4 out of 5 stars 250 reviews

53,683 users

A Statusbar with speed, percentage, time and loaded size (similar to Opera's one)
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