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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!

Rated 5 out of 5 stars (2)
1,809 users

Live HTTP Headers (Fixed By ITWorld.com.pk)

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 (5)
2,070 users

about:addons-memory 2016 No Restart

Adds a new page that shows add-on memory usage

Rated 5 out of 5 stars (16)
5,984 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)
84,293 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)
1,487 users

HttpFox

An HTTP analyzer addon for Firefox

Rated 4 out of 5 stars (168)
93,616 users

JSONovich No Restart

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

Rated 4 out of 5 stars (35)
10,318 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 (70)
37,166 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)
28,645 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)
2,175 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)
16,530 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 (453)
296,883 users

User Agent Changer

Adds a menu and a toolbar button to change the user agent of a browser.

Rated 4 out of 5 stars (6)
2,884 users

Element Inspector No Restart

In the DOM Inspector,quickly navigate to the any elements

Rated 5 out of 5 stars (28)
3,499 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)
19,556 users

Screengrab (fix version)

Screengrab! saves webpages as images.
0.99 released!
New features: upload to internet

Rated 5 out of 5 stars (291)
147,385 users

Web Developer

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

Rated 5 out of 5 stars (235)
512,097 users

Live HTTP Headers

View HTTP headers of a page and while browsing.

Rated 4 out of 5 stars (168)
158,666 users

Click-to-Play Manager No Restart

Manages the Click-to-Play domain whitelist.

Rated 4 out of 5 stars (11)
3,349 users

SQLite Manager

Manage any SQLite database on your computer.

Rated 5 out of 5 stars (50)
206,479 users