Profiles are separate browsing profiles that run independently of each Each profile has its own bookmarks, settings, add-ons, browser history, cookies, and other data.

Mozilla Firefox now allows you to manage profiles while it’s running, without the need for using the Profile Manager found in older versions. To access this feature, type “about:profiles” in Firefox’s address bar, and then press Enter. You can bookmark this page for easier access in the future if you like.

If you haven’t fiddled with Firefox profiles before, you will likely be using the “default” profile.

To create a new profile, click the “Create a New Profile” button.

The wizard walks you through the steps of creating a new profile in Firefox. You may select a custom name for the profile. For example, you might name it “Work” if it’s for work.

To relaunch Firefox with your new profile, first, click the “Set as default profile” button before you finish. Once it’s your default profile, close all open Firefox browser windows and then relaunch Firefox. It launches with the default profile you chose.

To switch back to another profile, head to about:profiles once again, click “Set as default profile” for the profile you want to use, and then close and relaunch Firefox.

If you don’t need a profile anymore, you can click the “Remove” button here to remove it from your system. Bear in mind that this will delete all the data saved with the profile, including its bookmarks, saved passwords, and add-ons.

Each profile is listed with its root directory and local directory, and whether it is the default profile of the browser. The default profile gets loaded automatically when you don't supply other instructions on start.

About five options may be displayed that you can activate for profiles:

  1. Rename -- always available. Renames the profile name.
  2. Open Folder -- always available. Opens the folder of the profile in the default file browser of the operating system.
  3. Remove -- only available for non-default and profile not in use. Deletes the entire profile. There is no backup but Firefox displays a prompt that requires confirmation and explains that the data cannot be restored once the user gives the okay.
  4. Set as default profile -- only available to profiles that are not the default. Changes the default Firefox profile to the selected one.
  5. Launch profile in the new browser (Firefox 63) -- Opens a Firefox instance using the selected profile.

Try this: Create desktop shortcuts to load profiles and different versions of Firefox with just a click.

How to Use Multiple Profiles At Once

You may have noticed that there is a “Launch profile in new browser” button on the “About Profiles” page. However, this button does nothing when using Firefox’s default configuration for handling profiles. By default, Firefox only runs a single profile at once. You have to close and relaunch your browser to switch between profiles. But, with a little modification to the shortcut you use to launch it, Firefox can run multiple profiles at the same time.

To enable multiple Firefox profiles at once, you must launch Firefox with the -no-remotecommand line option. To do this, you need to edit the taskbar, desktop, or Start menu shortcut you normally use to launch Firefox.

For example, if you use the taskbar shortcut to launch Firefox, right-click the Firefox icon on the taskbar, right-click “Mozilla Firefox” in the popup menu, and then select the “Properties” option.

In the properties window, on the “Shortcut” tab, place your cursor at the very end of the text in the “Target” box, and then add -no-remote to the end of the text. The Target box should look something like:

"C:\Program Files\Mozilla Firefox\firefox.exe" -no-remote

Click “OK” to save your changes.

Close all open Firefox browser windows, and then relaunch Firefox using the shortcut you just modified. When you do, you can head back to the about:profiles page and click the “Launch profile in new browser” button. Firefox opens a new browser window with the profile you selected.

If you need help telling which is which, you can always head to menu > Add-ons > Themes and set a different theme for each profile.

Use the Old Profile Manager Instead

You can also do everything with the old Firefox Profile Manager if you prefer. This also lets you create special shortcuts that open Firefox’s Profile Manager and launch Firefox with specific profiles if you like.

First, you need to close Firefox completely. Next, you’ll need to launch Firefox with the -pswitch.

  • On Windows: Press Windows+R, type firefox.exe -p into the Run box that appears, and then press Enter.
  • On Mac: Open a Terminal window—press Command+Space, type Terminal, and press Enter to do it from Spotlight. At the prompt, type /Applications/Firefox.app/Contents/MacOS/firefox-bin -profilemanager and then press Enter.
  • On Linux: Open a terminal and run the firefox -profilemanager command.

You’ll see the Choose User Profile dialog window. By default, there will be a single user profile named “default.” You can use this window to create additional profiles, rename existing ones, and delete them.

If you’d like to always see the profile chooser when you start Firefox—this would let you choose a profile each time you click your Firefox shortcut without requiring a special command—you can turn off the “Use the selected profile without asking at startup” option. This causes Firefox to ask which profile you want each time you start it—at least until you turn that option back on.

You need at least one profile to use Firefox. Each profile has its own settings, extensions, bookmarks, history, cookies, and everything else. Bear that in mind. If you delete the “default” profile, you’ll lose all your Firefox browser data (unless you’re using Firefox Sync and can get it back from there.)

When you create a new profile, you can give it any name you want. The wizard shows you where the profile will be stored. By default, they’re placed under your user account’s Firefox profiles folder, prefixed with eight random letters and numbers.

Select a profile, and then click “Start Firefox” to start Firefox with that selected profile. When you start Firefox for the first time with a new profile, you’ll see the welcome experience again.

Quit Firefox and launch it again to switch between profiles. Assuming you turned off the “Use selected profile without asking at startup” option, Firefox asks which profile you want to use before launching. You could also leave that box checked and launch Firefox with the -p or -profilemanager switch to access the hidden profile manager when you want it.

For ease of use, you could create a shortcut that opens Firefox with the profile manager, too. For example, on Windows, you could create a copy of the Mozilla Firefox shortcut on your desktop, rename it something like “Mozilla Firefox – Profile Manager”, and then add a space and a  -p to the end of the text in the “Target” box. That shortcut would now open Firefox with the Profile Manager, assuming Firefox is completely closed when you launch the shortcut.

Firefox isn’t set up to work quite like Chromium by default. It only wants you to use a single profile at once. However, you can use multiple profiles at once, if you like.

To do this, you’ll just need to launch Firefox with the -no-remote switch. You could do this from the Run dialog or terminal or just modify an existing Firefox shortcut. For example, if you created the Profile Manager shortcut above, you could just add -no-remote so that it reads -p -no-remote at the end of the Target box.

Launch Firefox with this switch—in other words, double-click the shortcut you just created—and it won’t check to see if Firefox is already running. Instead, it’ll ask which profile you want to use and create a new Firefox process with that profile.

You can use this process to open Firefox with as many different profiles as you want, although each profile can only be in use by one copy of Firefox at a time. If you try to open the same profile a second time while it’s already running, you’ll see a “Profile In Use” error.

Note: If you see a profile in use error while Firefox appears to be closed, you may need to visit the Task Manager and kill the firefox.exe process from there, forcibly closing it if it’s stuck running in the background.

This should all work like you’d expect it to. However, while Chromium-based browsers they make it easy to see which profile you’re using (top right corner,) Firefox doesn’t make visible. For that, you might want to install a different theme for each profile or visually distinguish them in another way.