Violentmonkey provides userscripts support for browsers. It's open source! https://github.com/violentmonkey/violentmonkey
★ Used by Several Million users on different platforms ★ 1) Screen capture web pages 2) Selected regions 3) Whole browser window 4) Slack upload Edit screenshots. Save images as local files or Google Drive. Tools for Annotation. Upload and share
Download PDF files directly from Scopus!
Easily override the browser's User-Agent string
DevTools for Redux with actions history, undo and replay.
Manage and switch between multiple proxies quickly & easily.
Selenium IDE is an integrated development environment for Selenium tests. It is implemented as a Firefox extension, and allows you to record, edit, and debug tests.
RESTClient has been completely rewritten for compatible with Firefox 57. Some functions are still missing (OAuth & OAuth 2.0 authentication).
Cookie-Editor lets you efficiently create, edit and delete a cookie for the current tab. Perfect for developing, quickly testing or even manually managing your cookies for your privacy. Also supports Firefox for Android.
WebRTC leaks your actual IP addresses from behind your VPN, by default.
Quickly and easily switch between popular user-agent strings.
A replacement for the Java Plugin so Java Applets without graphics continue to work on browsers that no longer support NPAPI plugins. Java's LiveConnect API is emulated — data & method calls can be exchanged, and Java can manipulate the webpage DOM.
Easy to use video and audio converter and muxer written in WebExtension built on top of the well-known FFmpeg converter
View JSON documents in the browser.
Blocks desired HTML contents (script, style, image, object, media)
A wrapper for Chengyin Liu's WhatFont tool
A firefox addon allowing the user to enable CORS everywhere by altering http responses. Report issues to the repository, with enough information to reproduce the problem: https://github.com/spenibus/cors-everywhere-firefox-addon/issues
An image extractor for sniffing, analyzing and batch downloading images from web page.
A tool for viewing SAML and WS-Federation messages sent through the browser during single sign-on and single logout.
This extension is very useful for PHP developers that are using PHP tools with Xdebug support like PHPStorm, Eclipse with PDT, Netbeans and MacGDBp or any other Xdebug compatible profiling tool like KCacheGrind, WinCacheGrind or Webgrind.
Allows URI texts written in webpages to be loaded by double clicks.
Re-enable the possibility to use the context menu on sites that overrides it
Accelerate your SEO efforts on the fly. SEOquake is a free plugin for browsers that provides you with key SEO metrics for a specific page, along with other useful tools such as SEO Audit and many others.
A REST client for the rest of us