Disable JavaScript
Adds the ability to disable JavaScript for specific sites or specific tabs. You can customize the default JS state (on or off), the disable behavior (by domain or by tab) and much more.
30,894 users
JavaScript Switcher
A lightweight addon that adds a Toggle button in URL bar, for toggling JavaScript (on or off) individually per domain, and stores that for future visit. Works also with Firefox 57+.
5,566 users
JavaScript Toggle On and Off (WebExtension)
Toggle JavaScript engine on and off the easy way
12,310 users
JavaScript Playground ⚡ Online JS Compiler
**Write and run JavaScript code instantly.** Skip the setup and open a distraction-free playground with a single click. Test functions, debug concepts, or learn new features right in a dedicated popup. just pure, instant JS code execution.
33 users
uBlock Origin
Finally, an efficient wide-spectrum content blocker. Easy on CPU and memory.
10,521,963 users
Chrome Mask
Makes Firefox wear a mask to look like Chrome to websites that block Firefox otherwise.
52,776 users
NoScript Security Suite
The best security you can get in a web browser! Allow potentially malicious web content to run only from sites you trust. Protect yourself against XSS other web security exploits.
238,924 users
Greasemonkey
Customize the way a web page displays or behaves, by using small bits of JavaScript.
154,388 users
HTML Runner
Run HTML, CSS, and JavaScript instantly in a new tab — no server, no build, no setup.
46 users
DuckDuckGo HTML Search (POST)
Adds DuckDuckGo HTML as a search engine for a non-JavaScript experience
242 users
Turn Off the Lights for Firefox
The entire page will be fading to dark, so you can watch the videos as if you were in the cinema. Works for YouTube and Beyond. Dark mode for all websites. It works for all known video sites such as YouTube, Vimeo, Twitch, Dailymotion, Facebook, etc.
63,261 users
WP Hive - A better WordPress Repository
Get useful metrics such as the impact on memory usage & pagespeed, PHP errors, warning, Javascript issues, PHP compatibility, latest WordPress version compatibility, database footprint, activation error, and more right from the WordPress repository
160 users
Web Injector
Customize any website by injecting your own CSS and JavaScript. Includes tools for Dark Mode and RTL text fixing.
19 users
Mobile DevTools
an extension that adds Eruda developer tools to Firefox Android. Lets you use the console, inspect elements, and network monitor on your phone
5,201 users
Customizer styles and scripts
Customize font size and styles of site. Extension give you able to change pages of sites on your choice, add custom javascript and run it on reload page, change font size, font color and any other styles with css syntax.
21 users
