Speed up the development process by using add-ons to troubleshoot, edit, and debug web projects without ever clicking away from Firefox.
Check for best practices and common errors with your site's accessibility, speed, security and more.
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.
Extends the Developer Tools, adding tools for debugging and profiling Angular applications.
A browser extension that lets you display the basic typographic styles of a text by right-clicking it.
Shows a report of browser compatibility issues using data from MDN
Server-side debugging via web console, substituting native support for the Chrome Logger protocol developed by Craig Campbell ( https://craig.is/writing/chrome-logger/ ) in Firefox 43 – 56.
The Web Developer extension adds various web developer tools to the browser.
Add accessibility auditing to the Firefox Developer Tools
Because good website security shouldn't only be available to mad scientists! Laboratory is an experimental Firefox extension that helps you generate a Content Security Policy (CSP) header for your website.
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.
Easily explore and debug any WebGL context.
DevTools for Redux with actions history, undo and replay.
DevTools extension for debugging Vue.js applications.
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.