How to Install Firefox Dev on Fedora

Firefox Developer Edition gives you access to upcoming Firefox features before they reach the stable release, along with specialized developer tools for web development. Whether you want to test new CSS capabilities, debug web applications, or preview performance improvements, this guide walks you through installing Firefox Developer Edition on Fedora using a community-maintained COPR repository. By the end, you will have Firefox Developer Edition running alongside your stable Firefox installation, complete with automatic updates through DNF.

Choose Between Firefox Developer Edition and Nightly

Mozilla publishes multiple Firefox channels, each with different stability and update schedules. Use the comparison below to decide which pre-release channel fits your workflow.

Firefox Channel	Update Schedule	Stability	Best For
Firefox Developer Edition	Almost daily (COPR tracks upstream)	Generally stable with newer features	Web developers who need reliable daily-driver browsers with advanced tooling
Firefox Nightly	1-2 times daily	May contain bugs or incomplete features	Early adopters, bug reporters, and those testing cutting-edge changes
Firefox Stable (pre-installed)	Every 4 weeks	Production-ready	General use where stability matters most

Firefox Developer Edition follows the Beta channel but includes additional developer-focused features enabled by default. The the4runner/firefox-dev COPR package tracks upstream releases closely, providing updates within days of new official builds.

What Firefox Developer Edition Offers

Firefox Developer Edition provides web developers with specialized tools and early access to new browser capabilities. Consider these practical reasons to install it:

• Enhanced Developer Tools: Inspect CSS Grid and Flexbox layouts, debug JavaScript with advanced breakpoints, and analyze network requests with detailed timing information.
• Early Feature Access: Test upcoming CSS features, JavaScript APIs, and browser capabilities before they reach stable Firefox, giving you time to update your projects for new web standards.
• Separate Profile: Firefox Developer Edition uses its own profile directory, so your stable Firefox bookmarks, extensions, and settings remain untouched.
• Dark Theme by Default: Developer Edition ships with a dark developer tools theme optimized for long coding sessions.
• Experimental Features Enabled: CSS features and APIs that require manual flags in stable Firefox are often enabled by default in Developer Edition.

Update Fedora Before Installation

Before adding any new repositories, ensure your Fedora system has the latest package updates. This prevents dependency conflicts and ensures your package manager cache is current.

Open a terminal by searching for “Terminal” in Activities, then run:

sudo dnf upgrade --refresh

The --refresh flag forces DNF to synchronize with remote repositories before checking for updates. If updates are available, review the package list and confirm the installation when prompted.

Enable the Firefox Developer Edition COPR Repository

Firefox Developer Edition is not available in Fedora’s default repositories or on Flathub. Instead, you will use a community-maintained COPR repository that builds Firefox Developer Edition packages for Fedora. COPR (Cool Other Package Repo) is Fedora’s equivalent to Ubuntu PPAs, allowing maintainers to build and distribute packages outside the official repositories.

COPR repositories are community-maintained and not part of the official Fedora distribution. Packages may vary in quality and are not held to the same security standards as official Fedora packages. Only enable COPR repositories from maintainers you trust.

Enable the Firefox Developer Edition COPR repository with the following command:

sudo dnf copr enable the4runner/firefox-dev

When prompted, type y to confirm. DNF will download the repository configuration and add it to your system. You should see output similar to:

Enabling a Copr repository. Please note that this repository is not part
of the main distribution, and quality may vary.

The Fedora Project does not exercise any power over the contents of
this repository beyond the rules outlined in the Copr FAQ at
<https://docs.pagure.org/copr.copr/user_documentation.html#what-i-can-build-in-copr>,
and packages are not held to any quality or security level.

Please do not file bug reports about these packages in Fedora
Bugzilla. In case of problems, contact the owner of this repository.

Do you really want to enable copr.fedorainfracloud.org/the4runner/firefox-dev? [y/N]: y
Repository successfully enabled.

Install Firefox Developer Edition

With the repository enabled, install Firefox Developer Edition using DNF:

sudo dnf install firefox-dev

DNF will resolve dependencies and show you a transaction summary. Firefox Developer Edition installs alongside your existing Firefox installation rather than replacing it. Confirm the installation when prompted.

Verify the Installation

After installation completes, confirm that Firefox Developer Edition is working by checking its version:

firefox-aurora --version

Expected output:

Mozilla Firefox 147.0b9

Your version number will differ based on when you install, as this COPR package receives frequent updates tracking upstream Developer Edition releases. The b suffix indicates this is a Beta-channel build, which is the basis for Developer Edition.

Launch Firefox Developer Edition

Launch from Terminal

You can start Firefox Developer Edition directly from the terminal:

firefox-aurora

The command is firefox-aurora because Mozilla historically used “Aurora” as the codename for this pre-release channel before rebranding it to Developer Edition.

To run Firefox Developer Edition in the background and free your terminal, append an ampersand:

firefox-aurora &

Launch from Applications Menu

For desktop users, Firefox Developer Edition appears in your applications menu after installation. In GNOME, open Activities and search for “Firefox Developer Edition.” Other desktop environments like KDE Plasma, Xfce, or MATE display the application in their respective menus under Internet or Web browsers.

Firefox Developer Edition uses a distinct blue icon to differentiate it from the standard orange Firefox icon, making it easy to identify in your application launcher.

First Launch Setup

On first launch, Firefox Developer Edition creates a separate profile from your standard Firefox installation. This means you start fresh without bookmarks, extensions, or saved passwords from your regular Firefox. If you want to sync data between installations, sign in to your Firefox Account within Developer Edition.

By default, Developer Edition enables additional developer-focused features like multi-line console input and CSS Grid highlighting. You can adjust these settings in Preferences under Developer Tools.

For a detailed list of what is new in each Developer Edition release, check the Firefox Developer Edition release notes on Mozilla’s website.

Manage Firefox Developer Edition

Update Firefox Developer Edition

Because Firefox Developer Edition is installed through DNF, it updates automatically alongside your other system packages. To manually check for updates:

sudo dnf upgrade --refresh

This command refreshes the repository metadata and upgrades all packages with available updates, including Firefox Developer Edition. This COPR package receives new updates almost daily as it tracks the upstream Developer Edition releases.

For automated updates, consider setting up DNF Automatic on Fedora to handle package updates without manual intervention.

Remove Firefox Developer Edition

If you no longer need Firefox Developer Edition, remove it with DNF:

sudo dnf remove firefox-dev

After removing the package, disable the COPR repository so DNF stops checking for updates from a source you no longer use:

sudo dnf copr disable the4runner/firefox-dev

Remove Firefox Developer Edition Profile Data

Removing the package does not delete your Firefox Developer Edition profile data, which includes bookmarks, extensions, cached data, and browsing history. If you want a complete removal, delete both the profile and cache directories.

The following commands permanently delete all Firefox Developer Edition profile data and cache. If you have bookmarks or other data you want to keep, export them first through Firefox’s bookmark manager.

rm -rf ~/.mozilla/firefox/*.dev-edition-default*
rm -rf ~/.cache/mozilla/firefox/*.dev-edition-default*

These commands remove profile directories created by Firefox Developer Edition while leaving your standard Firefox profiles and cache intact.

Troubleshooting

COPR Repository Enable Fails

If the dnf copr enable command fails with a connection error, verify your internet connection and try again. The COPR infrastructure occasionally experiences high load. You can also manually check the repository status at the the4runner/firefox-dev COPR page.

Firefox Developer Edition Crashes on Launch

Developer Edition builds may occasionally have stability issues. If Firefox Developer Edition crashes immediately after launching, try starting it in safe mode to disable extensions:

firefox-aurora --safe-mode

If safe mode works, an extension may be causing the crash. You can also try creating a fresh profile:

firefox-aurora --ProfileManager

This opens the profile manager where you can create a new profile for testing.

Audio or Video Playback Issues

Some multimedia codecs may not work correctly in Developer Edition builds. If you experience audio or video playback issues, ensure you have the necessary codec packages installed. The ffmpeg-free package from Fedora’s default repositories provides open-source codec support:

sudo dnf install ffmpeg-free

For proprietary formats like H.264 and AAC, you need additional packages from RPM Fusion. After installing codecs, restart Firefox Developer Edition to apply changes. For more information on DNF package management, see our DNF5 install examples guide for Fedora.

Graphics or Display Problems

Firefox Developer Edition sometimes introduces experimental graphics features that may not work correctly with all hardware. If you experience rendering issues, crashes related to graphics, or screen flickering, you can disable hardware acceleration:

1. Open Firefox Developer Edition and type about:preferences in the address bar
2. Scroll down to Performance
3. Uncheck “Use recommended performance settings”
4. Uncheck “Use hardware acceleration when available”
5. Restart Firefox Developer Edition

For NVIDIA users experiencing issues, ensure your NVIDIA drivers on Fedora are up to date.

Conclusion

Firefox Developer Edition is now running on your Fedora system with access to upcoming browser features, enhanced developer tools, and a separate profile from your stable Firefox installation. The COPR repository handles updates automatically through your regular dnf upgrade maintenance, so you always have the latest Developer Edition build. To get the most from Developer Edition, sign into your Firefox Account to sync bookmarks and settings across installations, then explore the enhanced DevTools by pressing F12 to inspect CSS Grid layouts, analyze network performance, and debug JavaScript with advanced breakpoints.