⚙ ʣ “Developer”

by zoding

21 Add-ons in this Collection

User Agent Switcher by chrispederick

Rated 4 out of 5 stars 336 reviews

158 users

The User Agent Switcher extension adds a menu and a toolbar button to switch the user agent of a browser.

SQLite Manager by lazierthanthou

Rated 4 out of 5 stars 354 reviews

84 users

Manage any SQLite database on your computer.

Live HTTP Headers by Daniel Savard, Nikolas Co

Rated 4 out of 5 stars 216 reviews

37 users

View HTTP headers of a page and while browsing.

Mozilla Archive Format, with MHT and Faithful Save by Christopher Ottley, Paolo Amadini

Rated 5 out of 5 stars 359 reviews

40 users

— Open web pages saved with Internet Explorer or other browsers (MHT)
— Save many tabs, video and audio reliably, in a single ZIP file (MAFF)
— Return to the original site you saved a page from, and more!

JavaScript Debugger by James Ross, Robert Ginda, others

Rated 4 out of 5 stars 52 reviews

931 users

As of Firefox 33, Venkman *no longer works*, as the APIs which it needs have been removed.

Venkman is the code name for Mozilla's JavaScript Debugger. Venkman aimed to provide a powerful JavaScript debugging environment for Mozilla based browsers.

Master Password+ by V@no

Rated 4 out of 5 stars 186 reviews

205 users

Various enhancements for build-in "master password" (MP)
-Locks master security device on demand or after specified time
-Prompts for MP on browser startup
-Suppresses all or duplicate MP prompts
-Locks up entire application or individual windows

Scriptish by Erik Vold, Nils Maier, others

Rated 4 out of 5 stars 109 reviews

11 users

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

WorldIP - Geo Add-on with Security Features by Alrond

Rated 5 out of 5 stars 124 reviews

21 users

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

Execute JS by Rudolf Noe

Rated 5 out of 5 stars 15 reviews

0 users

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

Key Manager by Subrata Mazumdar

Rated 3 out of 5 stars 21 reviews

0 users

KeyManager Tool: Firefox Add-on for Key Generation, Certificate Enrollment, CRL Signing, and Identity and Authority Delegation

Markdown Viewer by Thiht

Rated 4 out of 5 stars 52 reviews

2 users

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

Tiny JavaScript Debugger by Patrick Brunschwig

Rated 5 out of 5 stars 8 reviews

57 users

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.

XHTML Mobile Profile by Gareth Hunt

Rated 4 out of 5 stars 12 reviews

1 user

Firefox does not natively support the mime-type application/vnd.wap.xhtml+xml. This is one of the possible mime-types for XHTML Mobile Profile. This addon adds support for this mime-type.

Extension Auto-Installer by Wladimir Palant

Rated 5 out of 5 stars 48 reviews

6 users

Important note: This extension will not work in Firefox 57 and above. Providing this functionality in Firefox is no longer possible, the extension is discontinued.

InspectorWidget by Sailfish

Rated 5 out of 5 stars 10 reviews

6 users

Adds toolbar button and context menus for invoking the DOM Inspector (DOMi) for either chrome or content elements.
  1. 1
  2. 2
Results 115 of 21

What are Collections?

Collections are groups of related add-ons that anyone can create and share.

Explore Collections