Forum der Gemeinschaft Firefox

Starting with Firefox 141, I noticed the profile folder is locked down by Mozilla by way of folder permissions, to the extent that I (as administrator) cannot even take ownership of the folder. Even after I completely uninstalled Firefox and restarted my computer I can't take ownership of the folder, nor can I delete it - access is simply denied. I have to literally boot up with a Linux Live distro to be able to delete it. This is invasive and NOT OK!!

I work with multiple profiles that require backups and be copied. I also have a 'master profile' which is set up to co contain all my settings and addons - when I require a new profile I simply copy it over and voila. Not even this is possible anymore, as Mozilla has locked down the entire folder tree, I can no longer copy a new profile into C:\Users\*USER*\AppData\Roaming\Mozilla\Firefox\Profiles.

I also cannot copy existing profiles (and therefore also not able to backup) out of C:\Users\*USER*\AppData\Roaming\Mozilla\Firefox\Profiles - access denied. This is uncalled for by Mozilla. I have complete removed Firefox from my computer, including registry entries, and even after that I'm still denied access and cannot even delete C:\Users\*USER*\AppData\Roaming\Mozilla.

The only solution to to any of the above issues is to either reboot into Windows Safe Mode or bootable media of another OS. But this is totally impractical - Mozilla cannot expect of me to stop all my work and restart my PC every time I need to perform any of the above mentioned issues.

This is highly invasive by Mozzilla - to not even be able to delete a profile folder without any trace of Mozilla on my computer???? Come on, FIX THIS !!!

Will Mozilla please provide the solution?

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)

This afternoon, I clicked on a link from an email and for the first time got a choose a profile pop-up. I do not want this; I have read info on Mozilla and elsewhere about its purpose but it doesn't say how to just stop the pop-up - there should be an option just stop the pop-up because I don;t want to have to choose amongst options. I have started copy-pasting the links in emails and going to Chrome and will seriously have to reconsider using Firefox of this continues. I don't want to have to type about:config or anything - this should have been an opt out or opt in thing and I want out. Thank you for your help.

Yes, I'd like to use the same account on both of my profiles.

I understand that for some users, this may be confusing.

In my case, the only reason for different profiles is that I need to use a Proxy Server for some websites, and no proxy for other websites. Manually switching proxy settings is painful, and doing so causes traffic for my other tabs/windows to go to the proxy, which I do not want.

I have a main (set of) windows (and its tabs) going straight to the internet, then I have a separate window (and its tabs) configured to go through a proxy (SOCKS5 in this case). I want all other settings, bookmarks, passwords, etc. to be identical to both. I end up having to logout of my main profile, log into the other profile to sync settings, log out of there, and log back into my main profile.

Is there a valid technical reason why an account on the same FireFox installation cannot be shared between two profiles?

I can do this on multiple computers (same account, different computers/profile), seems odd it is restricted to not allow on the same computer.

I have an alternative solution: Install FireFox natively, then install FireFox as AUR or FlatPak, but not sure this will collide as this both uses the same profile directory. Hum...

Wayne

At startup, Firefox starts with an account setup screen. I have been using current setup for 3 years. Tried troubleshoot mode to no avail. Had same problem 3 years ago.

Firefox created a new Profile for me during a recent update and ignored the Profile I had been using for many years.

That probably occurred because Firefox couldn't find the original Profile. I had moved it to C:\0-FFox\ to shorten the length of file names. I had been getting File-Name-Length errors, which ended after moving the Profile closer to C:\.

Now I can't access or use the original Profile. I've researched the ins and outs of Profiles but can't find a solution to this problem. I want to add my old Profile to the new Profile created by Firefox and maybe switch between the two, or maybe revert to using only the old Profile. But I can't figure out how to do that. Adding a Profile seems to imply adding a new Profile and not an old one.

I sincerely hope you can help me solve this problem!

Many thanks! Wayne

Could someone help me start over again and get it right, instead of a mess? Is it possible to somehow start from scratch or fix what I am doing wrong? Is there some way to open a new account and dump the mess I'm facing now?

I have 3 different profiles on my Desktop Firefox, and I'm able to change between them and even set some commands on CLI to switch between them easily, opening one or another.

Now, my question is: How can I do such a thing on mobile? I only linked my main account, and as far as I understood, I cannot link to multiple and switch on demand. Is there any way? Am I missing something?

I checked the tutorial on how to setup profiles and the profile manager doesn't seem to exist on mobile.

Thank you for your attention!

This is Firefox 142.0.1 on Windows 10. I prefer to have a local copy of the Firefox profile saved to a USB stick as a simple backup and for copying to another PC if necessary. I have been doing this for years, but now I am unable to do so because Windows gives me an "access denied" error for all of the files in the top-level profile directory. I cannot even open them in Administrator mode. If I try to copy the profile directory as described in your help pages, it says that I need permission from the account that I am logged in as in order to access the files! I have been using Windows since version 3.0 and I cannot understand what Firefox has done to make the profile inaccessible to everything but itself. Obviously, Firefox is able to read the files without additional permissions, so why can't I?

I have my personal account on firefox and it syncs everything but I want to be able to do the same for my business account. when I sign out of my personal and try to sign in to my business it says I can't. I try to re-set my password and it says I have to use the "primary" account email. It does not accept my business account.

How do I get firefox account for my business email?

Thank you

The article explaining why one should not downgrade ignores a critical reason why one needs to downgrade and that is when it turns out that the new version breaks an existing website!

I got bitten by this when Firefox "upgraded" me to V143 after which point the ticket system I use to support my customers stopped working. That same ticket system continues to work fine in Safari, Edge, Chrome and Brave, etc.

Worse, when one does try to downgrade, the old profile gets removed which means you lose EVERYTHING you had (tabs, bookmarks and presumably all the settings and saved passwords, etc). You need to be keeping the old profiles around so that they can be accessed again should someone NEED to downgrade. Fortunately I was able to use Time Machine to recover the old profile --- but somebody just didn't think this through.

Much as I have loved Firefox over the years, I'm starting to feel that it's time to give up on it and move to something else.

Turning off automatic updates is not a solution because eventually one will choose to upgrade manually and most people won't remember to make a copy of their existing profile. Should one then encounter a problem, you're back to square one

Very disappointing .

I am using a very old system that is running out of storage space. There is an 8.73 GB folder that I would like to empty to free up space. C:\dtemp\Profiles contains several folders that were created 10.27.21: 2qzfs15q.default, eybandys.default, f81zrqic.default-release, pctnmazu.default-release-1, and yns5cb3s.default-release.

Can I delete any of these folders?

I don't have a Profiles menu under the Account button on the main toolbar. My Firefox was just updated and the update tab info talked about the new profiles feature as if it was available. Is this rolling out in phases or should I be seeing it?

I have version 144.0, updated on 10/14/2025.

Thanks.

Hello, I have two profiles, one for work and one personal. I used two different email addresses for them. How can I merge these together for the new profile management?

Hello,

I received a popup tab about creating separate profiles. I am still not seeing an option to create another profile, in my case keep personal and work browsing separate on my work computer. The articles I have read do not seem to fit my situation. Firefox is up to date. Thank you for your help.

Do I have to be logged into an account to use profiles? I'm on my work computer on which I don't log into my account and "Profiles" option does not show up on my toolbar.