Forum der Gemeinschaft Firefox

Mozilla made an update of my Firefox installation on my Win11 laptop. all my password disappeared as well as my history and bookmarks.

I have now a virgin installation and is starting from scratch.

Now I get this error message: "This profile was last used with a newer version of this application. Please create a new profile." I deleted met shortcut and I opened Firefox by using Windows search. Now I see 4 profiles! I think I do not need to create a new profile. Maybe delete 3 of them ? What to do ? And, how?

Hi,

My Firefox had auto updated to the newer version with AI built-in and auto-enabled, which meant the browser would crash EVERY. SINGLE. TIME. I would launch it.

For perspective, I am running an old Lenovo Thinkcentre mini PC with an Intel i5 6th gen and 16gb of ram; its got Windows 11 installed, and always running out of memory with the simple things like browsing and word processing. This is NOT a PC or use-case that needs or warrants AI.

So, I uninstalled Firefox (149) and installed the latest version WITHOUT AI built-in (147).

I then synced my profile, and things ran fine. An hour passed, and then i kept getting an error, saying my profile was created with whatever and I need to create a new profile.

So, I created a new profile and synced, again, and I got the error, AGAIN...

I'm about to boycott Firefox on all the devices I control, and opt for an older version of Opera or something more obscure, so that I don't have to deal with this nonsense.

I created a new profile on my account. Whenever I am in the original profile, I can click on the new profile and it will open a new window with a new icon. However, I notice that under the new profile, it is not signed in. When I try to sign in, I get an error that says

Account already in use xxx@gmail.com is already signed in to the “original” profile

You can only associate this account with one profile on this computer.

Then it forces me to switch back to the original profile. This tells me that the profile is not syncing for access across devices.

This is happening on my macbook.

I have switched OS, from Windows 10 to Linux Mint, and wanted to copy the Firefox profile to the new OS. I tried using this guide: https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

I copied the xxxxxxxx.default-release folder, then switched OS to Linux Mint. After copying the files from the backup folder into the new folder, Firefox launches, but is completely blank. See the attached image. None of the buttons work, nor does the address bar or new folders. I also tried logging in to my Firefox account before copying the files, but that didn't work either.

Default Firefox works fine.

I was positively surprised recently when the new Firefox profile manager (about:profilemanager) was introduced. https://www.tech2geek.net/how-to-use-the-new-updated-profile-manager-in-firefox-2025/ is an article about that.

However, I thought it's just a new visual UI with an in-browser switcher for the existing profiles (that I already had setup). However, it does not appear so.

The differences I see:

1. 1. 1. old profile management

• was managed by `about:profiles` or when starting FIrefox with `-P`
• is saved in `~/firefox` and the `profiles.ini` clearly and quite obviously mentions them there, so it's easy to manage them.

I also found this old support article: https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles

1. 1. 1. new profile management

• automatically asks on startup if more than one profile exists
• is managed by `about:profilemanager` or with the Firefox burger menu
• seems to be saved in `~/.mozilla/firefox/Profile Groups` (Linux path here) in some .sqlite files, and I do not quite understand the format. Not mentioned in `profiles.ini`.
• also, when you change something here (even like opening a profile?), you cannot open `about:profiles` anymore, because it says "Some Firefox process has made changes to your profile, […] you need to restart Firefox", only after a restart further changes would be possible, which I find quite confusing but it also indicates somehow the features belong together?

And this seems to be the new one: https://support.mozilla.org/en-US/kb/profile-management#w_whats-the-difference-between-profiles-and-multi-account-containers

1. 1. Questions

• What are the differences here (I may have missed)?
• How can the new profile feature save so few files? Is it technically called "profile groups"?
• And the most important: How can I migrate an old profile? (In order to use the new features and GUI etc. I quite like)

Since the new "feature" profiles came out, I now always have this "originalprofile" in the browser (in the title bar) and in the Windows taskbar... It's really annoying.... Now my question is, how do I get rid of it again... on 3 more pictures, Firefox language is German...

Linux User So. I recently followed a Mozilla guide, previously posted, and something that I did, or changed, I now have a very annoying "profile" name in the title bar. Further to that, I now have an additional menu option called "Profiles", with --"profile --Add Profile

Manage Profiles

I have never had or seen these items, except when I've moved my profile from an old computer to a new computer, using the console of "firefox -P" command.

It is becoming very annoying as I only have one profile, and I don't want an more.

Question. How to I block the display of 'profile information' ? Thanks

I'm trying to configure Firefox on Mac using our MDM. The goal is ultimately to control a bunch of settings, but I'm trying to start simple by just installing the 1Password extension.

When I deploy this .mobileconfig file, nothing seems to happen to Firefox. I made this by following the example at https://github.com/mozilla/policy-templates/blob/master/mac/org.mozilla.firefox.plist but it doesn't seem to work and I am not sure how to debug.

<plist version="1.0"> <dict> <key>PayloadContent</key> <array> <dict> <key>PayloadContent</key> <dict> <key>org.mozilla.firefox</key> <dict> <key>Forced</key> <array> <dict> <key>EnterprisePoliciesEnabled</key> <true/> <key>Extensions</key> <dict> <key>Install</key> <array> <string>https://addons.mozilla.org/firefox/downloads/latest/1password-x-password-manager/latest.xpi</string> </array> </dict> <key>PasswordManagerEnabled</key> <false/> <key>ExtensionUpdate</key> <true/> </dict> </array> </dict> </dict> <key>PayloadEnabled</key> <true/> <key>PayloadIdentifier</key> <string>e441f671-148a-4039-a45d-12514e6d92b2</string> <key>PayloadType</key> <string>com.apple.ManagedClient.preferences</string> <key>PayloadUUID</key> <string>e441f671-148a-4039-a45d-12514e6d92b2</string> <key>PayloadVersion</key> <integer>1</integer> </dict> </array> <key>PayloadDescription</key> <string>Installs the 1Password Firefox extension for ease of use.</string> <key>PayloadDisplayName</key> <string>1Password Firefox Extension</string> <key>PayloadIdentifier</key> <string>77dc9f8b-aaee-4f91-93ba-30b81cc6a31b</string> <key>PayloadOrganization</key> <string>Exogee</string> <key>PayloadRemovalDisallowed</key> <true/> <key>PayloadScope</key> <string>System</string> <key>PayloadType</key> <string>Configuration</string> <key>PayloadUUID</key> <string>77dc9f8b-aaee-4f91-93ba-30b81cc6a31b</string> <key>PayloadVersion</key> <integer>1</integer> </dict> </plist>

Hello I got a pop up or it was new tab informing about new firefox functions. It was about profile creation and management. Now i have two profiles and cant switch back to my old one. I cant seem to be able to delete new profile to return to my old one.

I'm setting up Firefox on a new computer. I haven't done this for a while and the interface has changed, so I'm not sure how it works.

I want to move my Firefox profile to a directory in the Documents library to simplify backup. Following the Mozilla instructions I found, I opened about:profiles and clicked the Create New Profile button. I deleted the contents of the directory that Create New Profile created and copied the contents of the default profile directory to it. The last step is to tell Firefox to use my new profile instead of its default.

But the about:profile page lists three profiles: default-release, default, and my new one. The first two have a Set as default profile button; the last does not. So it appears that I can tell Firefox to use the default-release profile or the default profile, but there's no way I can tell it to use my new profile. I can only Launch profile in new browser -- presumably something I'll have to do every time I run Firefox.

This makes no sense. How can I tell Firefox to use my new profile -- not to launch a new browser with it, but to use it, period? If I can't, why can't I? Every version of Firefox I've ever installed up to now allowed this.

Also, the default-release profile section of about:profiles has the note "This is the profile in use and it cannot be deleted." So it appears that Firefox uses the default-release profile instead of the default profile as its default profile. What is the default-release profile? Why isn't the default profile the default profile?

I created multiple profiles with the new [management] feature. Amazing, I've been waiting for it for years!

If I open all my profiles I can distinguish them since they all have a different icon. I can also pin all the profiles (Keep in Dock) to the MacOS dock.

When I quit all Firefox instances, I would like to be able to immediately jump back to the desired profile.

Instead I get multiple Firefox icons (without the icon profile, that disappear after I quit Firefox). I find this inconvenient.

As the title says, when i go to about:support, and click the open profile folder, i wanted to install a customization to allow me to edit the default tab background, but for some reason i do not have admin privileges in that folder, i can't access anything, i can't edit anything nor create a new folder, even rename it. It says that my own computer does not have admin privileges inside that folder.

I regularly back up my profiles folder (desktop running Windows 10) and observe a steadily-increasing number of files. Where/what are they? If cookies, I really don't want to delete all cookies, but neither am I interested in manually going through the list and deleting individual ones. I realize we're not talking about a major storage space issue (~ half a gigabyte) -- just curious.

In "manage profiles" I see where to delete the extra profile that was created and I don't want. Thanks to Cetaseus1. my question is does deleting a profile delete all the bookmarks? there is an info box that warns that bookmarks will be deleted including my 30,000+ bookmarks that were rolled over to this unwanted profile that just appeared. My intent is to have one remaining profile and all my bookmarks. I am hesitant to delete a profile and loose all those bookmarks. I won't delete until Mozilla assures me that I won't lose the bookmarks in the other profile. Thanks.

A couple of days ago I noticed that Firefox had started using "Profiles". I do not want a profile. When I wanted to open firefox a window popped up asking me to pick a profile. I deleted my account. Now Firefox will not let me use it because I don't have a "Profile". If I cannot use firefox without a profile, which I never had to do for umpteen years, then I well switch to Chrome.

Unimportant and mildly disruptive issue: I've been using the about:profiles method to maintain separate profiles. I am aware that this is distinct from the new way to manage profiles (about:profilemanager; https://support.mozilla.org/en-US/questions/1543697 ).

I normally use my default profile (let's call it profile A) to open other profiles (of which there are 6 + a Nightly profile).

However, recently I've noticed that if I open another profile (B) from profile A: Refreshing profile A's about:profiles makes it inactive, with the "Another copy of Firefox has made changes to profiles" error. Now, B's about:profiles correctly displays the different profiles, and I can launch more profiles from here. But A is still shown as the default profile. I've tried this with a few other profiles (C, D), but even with those open, B still seems to have the functional about:profiles page.

Is there any way to reset this, i.e. to make A's about:profiles functional even when profile B is launched?

Edit: I think this is because profile B has the new profile manager enabled, and under this, B is the original profile. I tried setting browser.profiles.enabled to false in the about:config settings but this doesn't seem to help. Oh well!

bold text I don't know what subject: Missing Profile?

Firefox says profile is missing. I found default profile under C:\Users\19pro\AppData\Roaming\Mozilla\Firefox\Profiles. How do I restore it to Firefox?

Thank you, Patricia Schmieg