Welcome to your new favorite browser. Get the latest features, fast performance, and the development tools you need to build for the open web.
A Glance on Tutorial for- how to install the Firebug in Firefox, Using Firebug, Check CSS, HTML, JavaScript codes & layouts of the current website you are viewing. How to Download and install Firebug for Firefox? To download and install the Firebug in your Mozilla firefox browser, there are two ways to open the Add-on web page in Firefox. Firefox Developer Edition is the blazing fast browser that offers cutting edge developer tools and latest features like CSS Grid support and framework debugging.
Firefox Developer Edition automatically sends feedback to Mozilla. Learn more
Faster Performance
A Next-Generation CSS Engine
Firefox Quantum includes a new CSS engine, written in Rust, that has state-of-the-art innovations and is blazingly fast.
New Tools
Firefox DevTools
The new Firefox DevTools are powerful, flexible, and best of all, hackable. This includes a best-in-class JavaScript debugger, which can target multiple browsers and is built in React and Redux.
Innovative Features
Master CSS Grid
Firefox is the only browser with tools built specifically for building and designing with CSS Grid. These tools allow you to visualize the grid, display associated area names, preview transformations on the grid and much more.
Convenient Features
Shapes Editor
Firefox DevTools has a brand new shape path editor that takes the guesswork out of fine-tuning your shape-outside and clip-path shapes by allowing you to very easily fine-tune your adjustments with a visual editor.
Faster Information
Fonts Panel
The new fonts panel in Firefox DevTools gives developers quick access to all of the information they need about the fonts being used in an element. It also includes valuable information such as the font source, weight, style and more.
Design. Code. Test. Refine.
Build and Perfect your sites
with Firefox DevTools
Inspector
Inspect and refine code to build pixel-perfect layouts.
Console
Track CSS, JavaScript, security and network issues.
Debugger
Powerful JavaScript debugger with support for your framework.
Network
Monitor network requests that can slow or block your site.
Storage panel
Add, modify and remove cache, cookies, databases and session data.
Responsive Design Mode
Test sites on emulated devices in your browser.
Visual Editing
Fine-tune animations, alignment and padding.
Performance
Unblock bottlenecks, streamline processes, optimize assets.
Memory
Find memory leaks and make your application zippy.
Style Editor
Edit and manage all your CSS stylesheets in your browser.
Speak up
Feedback makes us better. Tell us how we can improve the browser and Developer tools.
Get involved
Help build the last independent browser. Write code, fix bugs, make add-ons, and more.
Thanks!
Install Firebug Addon
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