Firefox version 138 introduces a redesigned Profile Manager that allows users to create, switch, and personalize multiple browser profiles directly from the main menu. This upgrade brings Firefox in line with browsers like Chrome, making it easier to separate browsing data, settings, and extensions for different tasks or users. The new system is initially hidden and must be enabled before use, but once activated, it offers a streamlined workflow for anyone seeking distinct browsing environments on a single installation.

Enable the New Profile Manager in Firefox

Step 1: Ensure your Firefox browser is updated to version 138 or later. The new Profile Manager is not available in earlier versions, so confirm your build by opening the menu and selecting Help > About Firefox. Update if necessary to access the latest features.

Step 2: Activate the new Profile Manager by modifying a configuration setting. In the address bar, enter about:config and press Enter. Accept the warning prompt to proceed to advanced settings.

Step 3: In the search bar, type browser.profiles.enabled. If the setting appears, double-click to set its value to true. If it does not appear, right-click, select “New > Boolean,” and create the preference with the value true. Restart Firefox to apply the change.

Step 4: Access the Profile Manager from the main menu. Click the hamburger menu (three horizontal lines) in the top-right corner of Firefox. Click the new “Profiles” or “Current Profile” section.

Step 5: Select “Manage Profiles” to open the profile management interface. Alternatively, you can type about:profilemanager in the address bar to open the Profile Manager directly in a tab.

Create and Customize a New Profile

Step 1: In the Profile Manager, select “Create New Profile.” A setup wizard will prompt you to enter a name for your new profile. Choose a descriptive name such as “Work,” “Personal,” or “Testing.”

Step 2: Choose a theme and avatar for the profile. Firefox offers a range of color schemes (Light, Dark, System Default, or custom themes like Marigold, Ocean, or Terracotta) and several avatar icons. These options help you quickly identify profiles in the menu and on the Windows taskbar.

Step 3: Complete the wizard to add the profile. The new profile will now appear in the list of available profiles, each with its own settings, history, bookmarks, and extensions. No browsing data is shared between profiles, so each environment remains isolated.

Switch Between Profiles

Step 1: To change profiles, click your profile picture or the “Current Profile” section in the Firefox menu. A list of all available profiles will be displayed, each with its unique name and avatar.

Step 2: Select the desired profile. Firefox will restart into the selected profile, loading its own extensions, bookmarks, and settings. This allows you to quickly move between work, personal, or other specialized environments without cross-contamination of browsing data.

Note: Only one profile can be active at a time in the current stable release. Running multiple profiles simultaneously in separate windows is not yet supported, but may be considered in future updates.

Manage, Rename, or Delete Profiles

Step 1: Open the Profile Manager via the menu or about:profilemanager. Each profile entry includes options to rename or delete the profile.

Step 2: To rename, click the “Profile name” field, enter a new name, and confirm. This changes only the display name, not the underlying data folder.

Step 3: To delete, select the “Delete” option at the bottom of the page. You may be prompted to remove the profile from Firefox while keeping its data, or to permanently delete all profile files. Use caution: choosing to delete files erases all bookmarks, passwords, and settings stored in that profile.

Step 4: To set a default profile, click “Set as Default” on the desired profile. Firefox will launch with this profile unless another is chosen at startup.

Alternative Methods for Profile Management

Before version 138, Firefox users managed profiles using command-line options or the about:profiles page. These legacy methods still work and may be useful for advanced troubleshooting or for users who need to manage profiles outside the main browser interface:

  • Launch the old Profile Manager by closing Firefox and running firefox.exe -P (Windows), /Applications/Firefox.app/Contents/MacOS/firefox -P (macOS), or firefox -P (Linux) from a terminal.
  • Use about:profiles in the address bar to access basic creation, renaming, and removal tools.
Note: The new Profile Manager interface and the old command-line Profile Manager operate independently. Profiles created in one may not always be visible in the other, depending on their storage paths and version compatibility.

Switching to the new Profile Manager in Firefox streamlines the process of setting up and maintaining separate browsing environments, reducing confusion and saving time for users who juggle multiple workflows. Regularly backing up important profiles and keeping Firefox updated ensures you maintain control and security across all your browsing sessions.