Google Lighthouse
Lighthouse is an open-source, automated tool for improving the performance, quality, and correctness of your web apps.
16,350 users
Yandex Search
Adds Yandex for search engines
16,078 users
SeoQuake SEO extension
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.
15,715 users
Text Link
Allows URI texts written in webpages to be loaded by double clicks.
14,400 users
RESTED
A REST client for the rest of us
14,241 users
My IP Hider VPN
My IP Hider VPN is number one tool for hiding your IP and unblocking any web site! If your Firefox version is less then 55 please install older My IP Hider VPN from "Version History" (https://goo.gl/7ZQQjZ)
14,131 users
Export Cookies
Export cookies to a Netscape format cookies.txt file.
13,613 users
JavaScript Toggle On and Off (WebExtension)
Toggle JavaScript engine on and off the easy way
13,593 users
Lightning Autofill
The most popular autofill extension, boosting productivity since 2010.
13,572 users
javascript
add javascript that will run on this domain. back up your scripts in the options area (shortcut there by clicking the "JS" letters in the bottom right)
12,948 users
Fake Filler
A form filler that fills all form inputs (textboxes, textareas, radio buttons, dropdowns, etc.) with fake and randomly generated data. The purpose of this extension is to help developers and testers test forms quickly and easily.
12,707 users
Mobile emulator
Smartphone emulator on computer very realistic with several models to test mobile websites.
12,459 users
Flag Cookies
A cookie and browser storage data manager on steroids to mark, 'flag', and manage cookies using rulesets.
12,002 users
JSON Lite
Fast JSON viewer - highlights, shows items count/size, handles large files
11,635 users
Empty Cache Button
Cache clearing made easy. One click.
11,276 users
Fonts Ninja
Speed up your design workflow!
11,235 users
Modify Header Value
Add, modify or remove a header for any request on desired domains.
11,136 users
IP Address and Domain Information
The Ultimate online investigation tool! See detailed information about every IP Address, Domain Name and Provider.
11,045 users
RESTer
A REST client for almost any web service.
10,822 users
Allow CORS: Access-Control-Allow-Origin
Easily add (Access-Control-Allow-Origin: *) rule to the response header.
10,780 users
axe DevTools® - Web Accessibility Testing
Add accessibility auditing to the Firefox Developer Tools
10,204 users
Angular DevTools
Angular DevTools extends Firefox DevTools adding Angular specific debugging and profiling capabilities.
10,160 users
Save Screenshot
Saves the current page as image file or copies it to clipboard.
10,085 users
Proxy Toggle
Toggle between direct connection and a single proxy server via a toolbar icon.
9,981 users
Imageye - Image downloader
Find and download all images on a web page.
9,631 users