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Live HTTP Headers (clone) No Restart

View HTTP headers of a page and while browsing.

This is an unofficial "Live HTTP headers" clone, mainly to fix the Replay feature!

Not yet rated
1,097 users

about:addons-memory 2016 No Restart

Adds a new page that shows add-on memory usage

Rated 5 out of 5 stars (12)
4,622 users

Cookie Exporter

Exports all cookies in IE manner.
Makes a Netscape standard cookies.txt file.
Very useful for WGET --load-cookies option.

Rated 5 out of 5 stars (13)
4,574 users

Remote XUL Manager No Restart

Manages the Remote XUL whitelist to allow websites and local files to load XUL content. For versions compatible with Firefox 41 and lower, see All Versions page below.

Rated 5 out of 5 stars (36)
75,722 users

Live HTTP Headers (Fixed By Danyial.com)

View HTTP headers of a page and while browsing.
Live HTTP Header Fix By Danyial ITs Working On Firefox Again Fixed Reply Problem

Rated 4 out of 5 stars (6)
1,409 users

Clear Cache and Data No Restart

Clears the browser cache and other selected storage.

Rated 3 out of 5 stars (3)
4,796 users

View Source

Shows all source files of a webpage.

Rated 4 out of 5 stars (6)
1,222 users

JSONovich No Restart

Pretty-prints JSON content in the browser for easy, unobtrusive viewing.

Rated 4 out of 5 stars (34)
9,550 users

Sharp Color Picker No Restart

A full featured color selector tool, to work with colors, and easily find the colors you want.

Rated 4 out of 5 stars (1)
2,045 users

Dafizilla Table2Clipboard

Mozilla applications allow to select rows and columns from a table simply pressing Control key and picking rows/columns with left mouse button.
The selection can be copied to clipboard but the original table disposition is lost making ugly results wh...

Rated 5 out of 5 stars (63)
18,327 users

jQuery

jQuery and jQuery UI embedded in browser

Rated 4 out of 5 stars (7)
2,675 users

Full Web Page Screenshots (♥♥♥♥♥)

FireShot makes full web page screenshots. Demo: http://bit.ly/RlBQMV

Screenshots can be quickly captured and:

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

* OS Windows only

Rated 5 out of 5 stars (452)
273,603 users

Element Inspector No Restart

In the DOM Inspector,quickly navigate to the any elements

Rated 5 out of 5 stars (27)
3,293 users

Font Finder

FontFinder is created for designers, developers and typographers. It allows a user to analyze the font information of any element on a page, copy any piece(s) of that information to the clipboard, and perform inline replacements to test new layouts.

Rated 4 out of 5 stars (69)
34,545 users

Firesizer

Allows you to resize the window to specific dimensions.

NOTE: Users of Firefox 29 and above must install "The Addon Bar" extension to use this, as Firesizer uses the add-on bar that has been removed in Firefox 29.

Rated 4 out of 5 stars (129)
26,566 users

Live HTTP Headers

View HTTP headers of a page and while browsing.

Rated 4 out of 5 stars (168)
150,581 users

Add-ons Manager - Version Number No Restart

Restores version numbers for all installed add-ons inside Add-on Manager on Firefox, Thunderbird and Seamonkey.

Rated 5 out of 5 stars (17)
1,343 users

Web Developer

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

Rated 5 out of 5 stars (231)
482,481 users

Scriptish

The greatest user script engine on the Internet (a fork of Greasemonkey).

Rated 4 out of 5 stars (117)
70,199 users

PrefBar

The all in one toolbar(item). Houses and manages bigger amounts of buttons (Clear Cache, Clear Cookies, ...), Menus (User Agent spoof...) and checkboxes (Javascript, Flash, ...). Extensible from online-database or with self created buttons.

Rated 5 out of 5 stars (39)
15,314 users