Web and Developer Tools


MR Tech Toolkit

(Formerly Local Install) The primary goal of this extension is to provide the tools needed to install and manage extensions and themes locally and tons of other features.

Note: With Toolkit 6.0 Auto Archiving is fully working in Firefox 2.0 and temp...

Rated 4 out of 5 stars (143)
54,506 users

Restartless Restart No Restart

This 15KB restartless add-on will add a "File" -> "Restart" menu item and a ctrl/cmd + alt + r hotkey to restart Firefox or Seamonkey.

Rated 5 out of 5 stars (181)
45,546 users

WorldIP - Geo Add-on with Security Features

Professional Geo Add-on with security features and advanced network tools. Anti-phishing. Protection against DNS spoofing and fake sites. All DNS records for domain. The real location of web server, country flag, extended information about datacenter

Rated 5 out of 5 stars (115)
43,167 users

Classic Toolbar Buttons No Restart

'Classic Toolbar Buttons' add-on restores old toolbar button ui (known from Fx 4-7s small view, Fx 4-12s large view & Tb 5-14) for current Firefox, Thunderbird and Seamonkey versions on Windows.

Beta builds on versions page!

Rated 5 out of 5 stars (144)
41,425 users

Nightly Tester Tools

Useful tools for the nightly tester.

Rated 4 out of 5 stars (191)
38,237 users

Tiny JavaScript Debugger

TinyJSD is a JavaScript debugger for privileged code running Mozilla products like Firefox, Thunderbird, SeaMonkey. It serves to debug the application as well as extensions written in JavaScript.

Rated 4 out of 5 stars (5)
37,957 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 (66)
35,896 users


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 (126)
32,759 users


Converts text links into genuine, clickable links...

Rated 4 out of 5 stars (307)
31,148 users

Form History Control

Manage form history entries (search, edit, cleanup, export/import) and easy text formfiller.

Auto-save text entered in any form while typing to allow fast recovery when disaster strikes.

Control for which webpage form history is saved or not.

Rated 5 out of 5 stars (78)
28,691 users

FoxyProxy Basic

FoxyProxy Basic is a simple on/off proxy switcher. More advanced features and configuration options are offered by FoxyProxy Standard.

Rated 4 out of 5 stars (31)
25,833 users

Open With Photoshop No Restart

Open With Photoshop is a new companion for web and graphic designers to open up any web image with Adobe Photoshop via a single and quick mouse click.

Rated 5 out of 5 stars (47)
24,374 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)
21,163 users

Open With

Quickly test out your web pages in Internet Explorer, Chrome, Safari, or Opera. Open With opens the current page in your other browsers with just one click. Add Open With to your menus, toolbars and developer toolbox today!

Rated 4 out of 5 stars (176)
20,138 users


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)
16,796 users


NoRedirect lets the user take control of HTTP redirects. It can be used to interdict an ISP's DNS search redirection hijacks, preview/screen "shortened" URLs (e.g., TinyURL), stop the annoying redirection of "smart" error pages, etc.

Rated 4 out of 5 stars (49)
12,868 users

Proxy Tool

Proxy Tool - Powerful, yet User-friendly proxy tool to manage your proxies and anonymity needs, including: 46M+ user agents (world's largest), 10 different spoofed HTTP referrers, auto-proxy rotation, plus many more. Developed by http://ProxyList.co

Rated 4 out of 5 stars (40)
11,793 users


Console² (pronounced Console Squared or Console Two) replaces the JavaScript Console with what could be the next generation Error Console. From v0.5 includes the Console Filter extension previously available separately from the Console² website.

Rated 5 out of 5 stars (49)
10,666 users

JSONovich No Restart

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

Rated 4 out of 5 stars (33)
10,058 users

Cookie Importer

Imports cookies from a textfile.
Reads Netscape standard cookies.txt files as exported by IE and others.
Very useful in combination with the Cookie Exporter add-on.

Rated 5 out of 5 stars (2)
8,804 users