Web Development

by ace999

12 Add-ons in this Collection

Firebug by Joe Hewitt, Jan Odvarko, others

Rated 4 out of 5 stars 2,063 reviews

1,783,201 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...

User Agent Switcher by chrispederick

Rated 4 out of 5 stars 276 reviews

297,822 users

The User Agent Switcher extension adds a menu and a toolbar button to switch the user agent of a browser.

Web Developer by chrispederick

Rated 5 out of 5 stars 258 reviews

399,897 users

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

ColorZilla by Alex Sirota

Rated 4 out of 5 stars 380 reviews

219,831 users

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

MeasureIt by Kevin Freitas

Rated 4 out of 5 stars 362 reviews

120,172 users

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

Image Zoom by Jason Adams

Rated 4 out of 5 stars 347 reviews

122,612 users

Adds zoom and rotation functionality for images...

Firefinder for Firebug by Robert Nyman

Rated 3 out of 5 stars 28 reviews

17,091 users

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

Dust-Me Selectors by brothercake

Rated 3 out of 5 stars 87 reviews

14,937 users

Dust-Me Selectors is development tool to remove unused CSS selectors.

ShowIP by ShowIP Dev Team

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Experimental

Rated 3 out of 5 stars 286 reviews

35,207 users

Show the IP address of the current page in the status bar. It also allows querying custom information services by IP (right click) and see location and avaiable vouchers for shopping sites. Additionally you can copy the IP address to the clipboard.

DNS Cache by djungowski

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Experimental

Rated 4 out of 5 stars 27 reviews

1,383 users

Allows you to disable and enable or manually flush the DNS Cache of Firefox (Notice: This addon is no longer maintained. If you'd like to update it for newer Firefox versions check out the Github repo: https://github.com/djungowski/ff-dnscache)

PageDiff by Khadir Abdul

Rated 4 out of 5 stars 15 reviews

1,612 users

Pagediff is a simple page compare application. It helps web developers and designers to see HTML-code(text) differences between web pages...
One can visit my site to download new version(new versions before release)

Library Detector by pbakaus

Rated 4 out of 5 stars 26 reviews

910 users

Detects what javascript libraries are being used on the current page and displays the result as icons with detailed tooltips in the statusbar.

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