Developer Tools

by Zulkarnain K.

52 Add-ons in this Collection

about:addons-memory by Nils Maier

Adds an about:addons-memory page that details add-on memory usage

DOM Inspector by SeaMonkey Council

Rated 5 out of 5 stars 65 reviews

154,520 users

DOM Inspector is a tool that can be used to inspect and edit the live DOM of any web document or XUL application. The DOM can be navigated using a two-paned window displaying a variety of different views on the document and all nodes within.

JSONovich by mjgiarlo, Will Elwood

Rated 4 out of 5 stars 33 reviews

11,088 users

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

GitHub Extension Installer by Diego Casorran

Rated 5 out of 5 stars 8 reviews

2,968 users

Install Browser Extensions straight from GitHub Repositories

Markdown Viewer by Thiht

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Rated 4 out of 5 stars 28 reviews

8,025 users

Markdown document viewer.
Allows to visualize formatted markdown documents in browser.

Rebrand by Mike Kaply

Rated 4 out of 5 stars 12 reviews

3,732 users

This wizard creates an XPI that rebrands Firefox, SeaMonkey or Thunderbird. You can change the brand name as well as the brand images and icons.

Execute JS by Rudolf Noe

Rated 5 out of 5 stars 13 reviews

6,346 users

Execute JS is a enhanced JavaScript-Console, where you can comfortably enter and execute arbitrary JavaScript-Code and modify functions...

Developer Assistant by Ted Mielczarek, Gavin Sharp, others

Rated 4 out of 5 stars 46 reviews

3,537 users

A suite of tools for developers.

JavaScript Terminal by Paul Rouget

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Rated 4 out of 5 stars 5 reviews

3,643 users

JavaScript Terminal for Firefox.

User Style Manager by Girish Sharma

Rated 4 out of 5 stars 24 reviews

2,001 users

Easiest way to Add and Manage Custom User Styles in Firefox.
Add, Edit, enable, disable and delete in-numerous User Style Sheets to redesign the Firefox and the Web.

Magnifier by Girish Sharma, Paul Rouget

Rated 4 out of 5 stars 8 reviews

2,008 users

A quick restartless magnifier to debug styles and web pages.

Foundstone HTML5 Local Storage Explorer by Foundstone Inc.

Rated 3 out of 5 stars 13 reviews

3,403 users

Foundstone HTML5 Local Storage Explorer allows for viewing, modifying and deleting of data items stored in the browser's LocalStorage. LocalStorage is a client side storage technology introduced in HTML5.

JavaScript Object Examiner by Chuck_Baker

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1,314 users

Display JavaScript object methods and properties for any available scope.

Console² by Philip Chee, zeniko

Rated 5 out of 5 stars 49 reviews

10,751 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.

CSSsir by Razum

Rated 5 out of 5 stars 18 reviews

2,977 users

CSSsir is easy and handy tool which allows you to generate cross-browser code for main CSS- rules in a few clicks.
This CSS3 generator will be useful not only for web-masters and designers but also for common users.
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