Feature Queries Manager
Manage and toggle CSS on a page behind a @supports Feature Query.
1.833 utents
webhint
Check for best practices and common errors with your site's accessibility, speed, security and more.
2.346 utents
Selenium IDE
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.
33.593 utents
Augury
Extends the Developer Tools, adding tools for debugging and profiling Angular applications.
1.190 utents
Fontanello
A browser extension that lets you display the basic typographic styles of a text by right-clicking it.
3.129 utents
ChromeLogger
Parses and displays messages from X-ChromeLogger-Data and X-ChromePHP-Data headers in DevTools Web Console facilitating server-side debugging via the Chrome Logger protocol ( https://craig.is/writing/chrome-logger/ ).
539 utents
Web Developer
The Web Developer extension adds various web developer tools to the browser.
70.225 utents
axe DevTools® - Web Accessibility Testing
Add accessibility auditing to the Firefox Developer Tools
10.224 utents
Laboratory (Content Security Policy / CSP Toolkit)
Because good website security shouldn't only be available to mad scientists! Laboratory is a WebExtension that helps you generate a Content Security Policy (CSP) header for your website.
1.831 utents
DevTools Media Panel
DevTools panel that displays technical details about media elements and webrtc on the current page; intended primarily for web developers to understand media playback issues on their sites, and for users to provide more informative bug reports.
1.641 utents
React Developer Tools
React Developer Tools is a tool that allows you to inspect a React tree, including the component hierarchy, props, state, and more. To get started, just open the Firefox devtools and switch to the "⚛️ Components" or "⚛️ Profiler" tab.
178.988 utents
