by Pascal Polleunus

5 Add-ons in this Collection

Firebug by Joe Hewitt, Jan Odvarko, others

Rated 5 out of 5 stars 1,842 reviews

2,022,082 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...

Web Developer by chrispederick

Rated 5 out of 5 stars 249 reviews

447,776 users

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

ColorZilla by Alex Sirota

Rated 5 out of 5 stars 312 reviews

248,272 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 170 reviews

138,847 users

View HTTP headers of a page and while browsing.

MeasureIt by Kevin Freitas

Rated 4 out of 5 stars 358 reviews

130,967 users

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

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