Go to Windows platform Display platforms icon
Go to Windows platform Go to Mac platform Go to Android platform
Firefox Developer Edition 154.0b4 (64-bit) icon

Firefox Developer Edition 154.0b4 (64-bit)

154.0b4
Mozilla Organization
5.0
88.1 MB size

Get the latest features, fast performance, and the development tools!

Firefox Developer Edition is a specialized version of the Mozilla Firefox browser designed specifically for web developers.

It provides advanced development tools, experimental web platform features, and enhanced debugging capabilities to help developers build, test, and optimize modern websites and web applications.

Unlike the standard Firefox browser, Developer Edition includes a dedicated developer profile, additional DevTools features, and early access to upcoming web technologies, making it an ideal browser for frontend developers and web professionals.


Features

Advanced Developer Tools

Firefox Developer Edition includes powerful built-in tools for analyzing and debugging websites, including:

  • Page Inspector
  • JavaScript Debugger
  • Web Console
  • Network Monitor
  • Performance Tools

These tools help developers identify issues and improve website performance.


CSS and JavaScript Debugging

Advanced debugging features allow developers to inspect and modify:

  • CSS layouts
  • JavaScript code
  • DOM elements
  • Page styles

It supports modern CSS technologies such as Grid, Flexbox, and container queries.


Responsive Design Mode

Test websites across different screen sizes and devices with built-in responsive simulation tools.

Developers can preview mobile layouts, adjust viewport sizes, and analyze responsive behavior without using external tools.


Experimental Web Technologies

Firefox Developer Edition provides early access to new web APIs, browser features, and platform improvements before they become available in the standard Firefox release.


Network and Performance Analysis

The integrated Network Monitor and Performance tools help developers analyze:

  • Loading speed
  • Network requests
  • Resource usage
  • JavaScript performance

WebAssembly and Service Worker Support

Includes debugging support for modern web technologies such as:

  • WebAssembly applications
  • Progressive Web Apps
  • Service Workers

Multi-Account Containers

Separate different browsing sessions and accounts within the same browser window, making it useful for testing websites with multiple user environments.


Dedicated Developer Profile

Firefox Developer Edition uses a separate profile from regular Firefox, allowing developers to install testing extensions and customize settings without affecting their main browser.


User Interface

Firefox Developer Edition features a developer-focused interface with a clean layout and optimized access to debugging tools.

The dark theme reduces eye strain during long development sessions, while the integrated DevTools panel provides quick access to essential development features.


FAQ

Is Firefox Developer Edition free?

Yes. Firefox Developer Edition is completely free and open-source software developed by Mozilla.

Can I use Firefox Developer Edition as my main browser?

Yes. It is stable enough for daily browsing while providing additional tools for developers.

Can Firefox Developer Edition run together with normal Firefox?

Yes. Developer Edition installs separately and maintains its own profile.

Are Firefox extensions supported?

Yes. Most Firefox extensions are compatible with Developer Edition.

What is the difference between Firefox and Firefox Developer Edition?

Developer Edition includes additional developer tools, experimental features, and a separate development environment designed for testing websites and applications.


System Requirements

  • Operating System: Windows 10 / Windows 11 (64-bit recommended)
  • Processor: Intel or AMD 1 GHz or faster
  • RAM: 2 GB minimum
  • Storage: About 200 MB free space
  • Internet connection required for updates

Pros

  • Free and open-source
  • Powerful built-in developer tools
  • Supports modern web standards
  • Separate developer profile
  • Excellent privacy features
  • Regular updates from Mozilla

Cons

  • Experimental features may occasionally be unstable
  • Some developer workflows are better optimized for Chromium browsers
  • Requires more memory than basic browsers

Conclusion

Firefox Developer Edition is a powerful browser built for web developers who need advanced debugging tools, experimental web technologies, and a dedicated development environment.

With built-in DevTools, responsive testing features, JavaScript debugging, and strong privacy protection, it is an excellent choice for frontend developers and anyone working with modern web applications.

For developers who prefer an open-source browser with powerful customization options, Firefox Developer Edition remains one of the best development browsers available.

Information about Firefox Developer Edition 154.0b4 (64-bit)

License Open Source
Op. System Windows
Category Internet
Language English + more
Author Mozilla Organization
permission icon Permissions Not applicable
Date 2026-07-31
Size 88.1 MB
File type Official Website

Apps recommended for you

Telegram for Desktop 7.2.7 icon
Speedy alternative to WhatsApp. Send Telegrams from any device!
Directory Opus 13.25 icon
For home users who need a simple, high-performance PC file manager
Vivaldi 8.1.4087.70 (64-bit) icon
An advanced browser made with the power user in mind
Firefox Developer Edition 157.0b2 (64-bit) icon
Get the latest features, fast performance, and the development tools!
Epic Privacy Browser icon
Epic Privacy Browser for Windows is a privacy-focused web browser that blocks trackers, ads, and enhances online security for anonymous browsing.
Telegram for Desktop 7.1.4 icon
Speedy alternative to WhatsApp. Send Telegrams from any device!
Whale Browser 4.39.410.14 icon
Simple way to sync between a desktop and a mobile! Awesome new browser!
mIRC 7.85 icon
A popular Internet Relay Chat client used by millions of people
NxFilter 4.7.5.5 icon
NxFilter is a DNS filter for blocking harmful or unwanted websites
OkayFreedom VPN 1.9.7.0 icon
Securely surf the web and unlock restricted content
TunnelBear 4.20.0.0 icon
A friendly, secure and private VPN
DataVare NSF to PST Converter Expert 2.0 icon
Smart Way to Export NSF files to PST format on Windows
Maxthon 7.5.3.2400 icon
A suite of state-of-art, cloud-powered web browsers
CloudMounter 3.8.2156 icon
Mount cloud storage as local drive on Windows computers!
PS5 Remote Play 9.5.0.8040 icon
Control your PlayStation 5 console from a Windows PC!
KakaoTalk for Windows 26.8.1.5315 icon
Offers a convenient sync between your Windows PC and mobile device
Chromium icon
Chromium for Windows is an open-source web browser that serves as the foundation for Google Chrome, offering fast browsing and robust security features.
Imo Messenger icon
Chat and video call seamlessly with Imo Messenger for Windows, the fast and secure messaging app designed for Windows PCs to keep you connected with friends and colleagues.
eM Client 10.4.5606 icon
Fast email client with full Gmail, Hotmail and other services synchronization
Easy Gamer Utility icon
Easy Gamer Utility for Windows is a performance optimization tool designed to enhance gaming experience by boosting system performance and managing resources.
Octoparse 10.0.2 icon
No.1 Automated Free Web Scraping Software for Windows PC
Multi Commander 16.2.0 Build 3210 (64-bit) icon
A multi-tabbed file manager that is an alternative to the Windows Explorer
Imo Messenger for Windows 1.5.6.2 icon
Imo is a popular online instant messaging tool for Windows PC
Cyberduck icon
Transfer and manage files securely with Cyberduck for Windows, the free FTP, SFTP, WebDAV, Amazon S3, Google Drive, and cloud storage client.