Firefox Community Forum

I'm running Firefox 122.0.1 on a Windows 10 desktop PC, with a profile which includes a userChrome.css file which makes several layout and cosmetic changes.

I also have a laptop (also Windows 10) which has an old Firefox 97.0.1 installation, and I'd like to make the same changes on this machine which I'm used to on the main computer. I copied my desktop profile to the laptop, to the same directory as its present profile, but when I rebooted Firefox the transferred profile wasn't recognised.

While doing the transfer I received error messages about some of the folders: Destination path too long. This despite the fact that the registry flag to accept extended paths is set to 1. I had to skip several folders in order to complete the transfer.

Could this be the reason why the new profile isn't being picked up? Or is it because the two Firefoxes are of different versions?

I'd be grateful for any thoughts. Many thanks.

HI there,

Glad you folks have included an update to the 'profiles'. However, I'm having trouble with it. I previously created two profiles using 'about:profiles' function. However, only of them has mapped on to the new profiles feature. When I try to add a profile in the new way to do it, I can only create a new one, I can't transfer a pre-existing.

See attachments. One shows the new profile manager with the 'work' profile. The second shows the 'about:profiles' with both 'work' and 'life'. How to I add 'life' to the new profile manager?

Hi all, I used to run two Firefox instances on the same computer, each one using a different account (as I mentioned in the Subject), but I don't remember how I managed this, so now that I moved to a new computer I can't reproduce it! Thanks for helping, if anyone knows. Regards, Mike

Hi,

I take a look to forums and docs but didn't find answer to it : just found informations about the use of firefox -P

Is there a way to change the defaults profile path.

For example, in the profiles.ini :

Name=default IsRelative=1 Path=Profiles/be7er9lz.default Default=1

this is a relative path referring to %appdata%\Mozilla\Firefox\[PathVariableValue]

Is there a way to change a config file or config to customise the path for all users a windows computer ?

For example :

setting this variable to \\nameofserver\Firefox\

will made all relatives profiles looking for : \\nameofserver\Firefox\[PathVariableValue]

without this option, I should be obliged to edit all users profiles.ini to change path to absolute

Thanks for your help

ludovic

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.

I recently reinstalled Debian 13 on my workstation. This included installing Firefox-esr from the Debian repositories so the version before and after the reinstall is the same. Despite this, Firefox refused to start until I created a new profile - insisting that my profile was from an older version.

To add insult to injury, it offers a method to import data from Chromium (which I use rarely) but not from a previous Firefox profile.

Firefox Sync works so far as it goes, but not everyone wants to use it. Importing from a local profile should be easier to implement than remotely syncing - especially given that Firefox clients may not be the same on different devices.

And, of course, the initial point is that Firefox should accept a user profile when it was created by the same version. After all, when I upgrade Firefox on Debian, I'm not required to create a new profile. Why should I be forced to do it when I reinstall the same version?

when I start firefox, it tells me the old one is running and to close it. i hit the close button and keep getting the same message. I have uninstalled firefox and reinstalled it and keep getting the same problem.

I had a problem where FF 140.0 would not update, and in trying to get FF yo update, I used a re-install tool to which I was pointed in my problem report. This caused FF to wipe out my configuration, and I lost all my windows and tabs. I have gone to

    \Appdata\Roaming\Mozilla\Firefox\Proifiles\abnfpged.default

cleared all of the data therein, and restored that directory from a backup I made last Monday. But I cannot get FF to use that directory. "about:profiles" shows only two profiles, but the Profiles directory has five profiles:

03/10/2026 09:39 AM <DIR> qf00ka5x.default 03/10/2026 09:39 AM <DIR> v842ceue.default-release 04/11/2026 09:16 PM <DIR> .. 04/11/2026 09:16 PM <DIR> . 04/12/2026 03:08 PM <DIR> abnfpged.default 04/12/2026 06:29 PM <DIR> jdfj91sd.default-release-1775960183850 04/12/2026 06:48 PM <DIR> f1jq4mlq.default

Only the profiles beginning with "j" and "f1" are seen in the "about:profiles" screenshot I have attached. And I have attached a screenshot of my profiles.ini file. Also, in the abnfpged.default directory I restored, where is the list of all of my open windows and tabs? FF used to keep that in a sessionstore.jsonlz4 file, but that file is only written when FF closes. I tried to save a copy when I was having problems, but I stored the copy in the same directory, which FF changed during the re-install process. Here is my profiles,.ini file:

[Install308046B0AF4A39CB] Default=Profiles/jdfj91sd.default-release-1775960183850 Locked=1

[Profile1] Name=default IsRelative=1 Path=Profiles/f1jq4mlq.default

[Profile0] Name=default-release IsRelative=1 Path=Profiles/jdfj91sd.default-release-1775960183850

[Install641D10338ABA448D] Default=Profiles/abnfpged.default Default=1 IsRelative=1 Locked=1

[General]

StartWithLastProfile=1

Version=2

[BackgroundTasksProfiles] MozillaBackgroundTask-308046B0AF4A39CB-defaultagent=lnvi5jn5.MozillaBackgroundTask-308046B0AF4A39CB-defaultagent

I have not worked with the ;profiles.ini file in many years, as my FF configuration has not had problems. Thanks.

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.

I switched to Firefox a few months ago and I've been using the "about:profiles" page to mimic chrome's profile feature. I have 3 profiles, each with their own Mozilla account. How can I migrate these to the new profiles system?

I have a bunch of profiles set up via "about:profiles". Some of these are associated with different Mozilla accounts, some are not. Today, I wanted to rearrange those profiles to put some older profiles that I do not use as often lower on the page than more recent profiles. I thought I remembered there being an overview text file that included a number for each profile, the folder that profile's information was stored in, etc. When I went looking for that file, I could not find it, so I went looking for help articles and discovered that there is a new profile management tool.

When I tried using the new profile manager via "about:profilemanager", none of my current profiles are visible, so I cannot use that tool to reorder my profiles.

I would be grateful if you could point me to an article explaining how to reorder the profiles in "about:profiles". If that is not possible, I would appreciate a help article explaining the rationale for making these two uses of the word "profile" distinct, the ways in which these profiles are different from each other, and how to transfer settings from the older version to the newer version. I have everything set up just the way I like it within my current profiles and really do not want to have to recreate them from scratch...

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

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?

Good day,

I'd like to start by thanking the Mozilla Firefox dev team for the newest iteration of the profiles feature. I think it's great.

One area where I think it could use improvement from usability perspective is a way to launch a specific profile via the right-click menu when using the taskbar icon. Currently, using the "Choose a profile when Firefox opens" only gives users the option to select the profile on the initial launch of Firefox. After that if the user opens a new window via the taskbar, the most recently opened profile is automatically chosen.

I managed to find a "hack" to add the requested capability. It seems adding an action to the "firefox.desktop" file in the "/usr/share/applications/" directory works the way I'd like it to.

Modifications to "firefox.desktop" Changed line 12 to: Actions=choose-profile;new-window;new-private-window;open-profile-manager; Added lines 529 - 534 (before Desktop Action new-window): [Desktop Action choose-profile] Exec=firefox --new-instance Name=Choose Profile Name[en_US]=Choose Profile Name[en_CA]=Choose Profile Name[en_GB]=Choose Profile

The end result is a new option available when right clicking the taskbar that opens the new profile selector. Screencaps of options before and after attached. I imagine that users will need to have the "Choose a profile when Firefox opens" enabled for this to work as expected, but would like someone from Mozilla to confirm this.

Would like to request that this option be built into Firefox going forward, so there's no need for users to "tweak" it to get this functionality.

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

I have an account with Chewy. When I try to access the link to "My Pet" I receive this message:

400 Bad request Your browser sent an invalid request.

I don't understand why or how to correct it.

Hi - I wanted to migrate all my changes made in the flatpak app to the aur version. I noticed the profile content has a different structure in both - aur and flatpak configs. And any attempts to replace profile content with the other resulted in browser ignoring these and initing new config files. Was wondering if my config can be ported over or thats not possible thanks.

I've used Firefox as my default for years and years. Yesterday I got some popover telling me I had to create a new profile or I'd lose all my Firefox data, history, bookmarks, etc. It would not let me avoid this. So I did. Still lost all my history, started over. Today it's doing the same thing. What's up? I don't want to move to Chrome.