Firefox includes a Troubleshooting Information page with some problem-solving tools, details about your Firefox installation and other technical data, such as any installed extensions, important modified preferences and graphics information. If you are getting help on the support forum, content you provide from this page can help resolve your Firefox issue.

To access the Troubleshooting Information page: Click the menu button , click Help, and select More Troubleshooting Information. You will be taken to a page with the address about:support. You can also access this page by entering about:support into the address bar.

Give Firefox a tune up

The Refresh Firefox feature can fix many issues by restoring Firefox to its default state while saving your essential information. Consider using it before going through a lengthy troubleshooting process.

Diagnose issues

You can restart Firefox in Troubleshoot Mode to temporarily turn off hardware acceleration, reset some settings, and disable add-ons (extensions and themes) that might be causing problems. See Diagnose Firefox issues using Troubleshoot Mode for more information.

Try clearing the startup cache

Firefox stores certain temporary data in a startup cache to improve startup speed. Clearing the startup cache and then restarting Firefox can sometimes fix various issues, such as mixed languages in the user interface after an update. This will not change your profile data or add-ons.

Copy to clipboard

You can copy the contents of this page to the Windows clipboardMac clipboardclipboard. Clicking the Copy raw data to clipboard button will copy the source data in Json format. Clicking the Copy text to clipboard button will copy a version of the same data in report format for further use. (For privacy reasons, the Application Basics Profile FolderProfile Directory line will not be copied.)

After copying, you can paste the information into another window for someone to see by clicking the Edit menu in the program you are using and then selecting Paste (or by holding down the CtrlCommand key and pressing V).

Application Basics

• Name: Tells you the name of the product you are using. In most cases, it should say “Firefox”.
• Version: Tells you which version number of Firefox you are using.
• Build ID: The code created automatically to identify the unique environment in which this Firefox installation was built.

• User Agent: In addition to your browser and its version number, the User Agent provides other details about your system, such as the operating system and version.
• OS: Shows your operating system.
• Application Binary: Shows where Firefox is installed.

• Enabled Plugins: Clicking about:plugins will take you to a page that lists your installed plugins. For more information, see Watch DRM content on Firefox and Use plugins to play audio, video, games and more.
• Build Configuration: Clicking about:buildconfig will take you to a page that will help someone understand if you are using a standard version of Firefox or a custom version.
• Memory Use: Clicking about:memory will take you to a page that shows memory usage. For more information, see this blog post.
• Performance: Clicking about:processes will take you to the Process Manager page. For more information, see Task Manager - see whether tabs or extensions are slowing down Firefox.
• Registered Service Workers: Clicking about:serviceworkers will show you whether or not the Service Workers feature is enabled and if any current Worker URLs are registered. Service workers are used for web enhancements such as push notifications.

• Multiprocess Windows: This shows you the number of Multiprocess Firefox windows (if any) and the total number of windows that are open.
• Fission Windows: This shows you the number of Site Isolation (Fission) windows (if any), the total number of windows that are open and the reason this feature is enabled or disabled. For example, when Firefox is in Troubleshoot Mode and one window is open, the entry will show 0/1 Disabled by safe mode.

• Enterprise Policies: This shows you if your browser is being managed by Windows Group Policy or a policies.json file. If enterprise policies are managing Firefox, clicking Active will show you a list of the policies that are currently active on Firefox.

• Safe Mode: This tells you whether or not Firefox is currently in Troubleshoot Mode.
• Profiles: Clicking about:profiles will take you to the Profile Manager.

Crash Reports for the Last 3 Days

This section lists crash Report IDs, if any, submitted by the Mozilla Crash Reporter during the last three days. Clicking one of the Report ID links will take you to a web page with details about that crash. Clicking the All Crash Reports link will take you to the about:crashes page listing all submitted crash reports. To get help with crashes, see Troubleshoot Firefox crashes (closing or quitting unexpectedly).

Firefox Features

Some features included in Firefox, such as Pocket and Screenshots, are installed as extensions so that they can be updated separately from Firefox. These extensions (sometimes called system add-ons) are not listed in the Add-ons Manager.

Add-ons

Extensions are Firefox add-ons that provide additional functionality to Firefox. This section lists the name of each extension, its version, whether it is enabled, and its ID string. For more information about troubleshooting extensions you have installed, see Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems.

Graphics

Firefox can use your computer's graphics processor to speed up the display of some pages with video and animation, which is called hardware acceleration, and to display WebGL content. This section provides information about your computer's graphics device and driver, and will tell you whether hardware acceleration and WebGL are enabled or not in Firefox. Note that graphics features may be disabled because of outdated graphics drivers. For help updating your graphics drivers, see Upgrade your graphics drivers to use hardware acceleration and WebGL.

Media

This section displays information about your system audio. The displayed information will include your operating system's preferred audio settings, as well as the audio input (such as microphones) and output (such as speakers or headphones) devices. From here you can also see the state of each device and some information about the audio format settings. For more information on fixing audio issues in Firefox, see What to do if Firefox won't play any sounds.

Environment Variables

In this section, you will see environment variables utilized by Firefox and their values, such as the MOZ_CRASHREPORTER_DATA_DIRECTORY variable that shows where crash report data is stored on your computer. Other environment variables, if set, can change how Firefox behaves. For example, Firefox downgrade protection can be bypassed by setting the environment variable MOZ_ALLOW_DOWNGRADE, as described in this Firefox for Enterprise article.

Experimental Features

This section shows whether features that are considered experimental are enabled or disabled. These features may be enabled in Firefox Beta, Developer Edition and Nightly but, in most cases, will be disabled by default in release versions.

Important Modified Preferences

In this section, you will see a list of settings that have been changed from their defaults. This information will help someone know how you have adjusted your installation of Firefox. For instructions on how to reset preferences to default, see Reset Firefox preferences to troubleshoot and fix problems.

Important Locked Preferences

In Firefox, it's possible to lock certain preferences so that they cannot be changed by the end user. This is common in enterprise environments. For more information about locking preferences, see the Customize Firefox using AutoConfig documentation.

Places Database

Firefox periodically performs maintenance tasks on your bookmarks and history database (also known as Places database). Use the Verify Integrity button to perform those tasks on-demand. If you're having any problems with bookmarks and history, the Verify Integrity tool might help.

Accessibility

This section shows if you have accessibility software enabled in Firefox.

Library Versions

This section tells you which versions of some runtime libraries are used.

Sandbox

For security and performance purposes, Mozilla created Project Electrolysis (often referred to as e10s) to implement a practice called sandboxing into Firefox. This ensures that web content is run in a separate process from the main Firefox program. This section of the troubleshooting information shows details about the sandbox security levels. See the Sandbox page on the Mozilla Wiki for more information on sandboxing in Firefox.

Internationalization & Localization

This section shows information about the language and regional preferences in Firefox and your operating system. For information about using Firefox language packs, see Use Firefox in another language.

Printing

The Clear saved print settings button in this section allows you to reset all modified print preferences. This might help fix printing problems in Firefox.

Modified print settings

This section lists modified print preferences.