Firefox Community Forum

I am not a native English speaker, so I used translation. Please excuse any awkward phrasing. I previously updated my Firefox to version 150, but my tabs kept crashing roughly every 5 minutes. To solve this, I tried installing the Firefox ESR version. However, my profile had already been upgraded to the new version format, so ESR could not read my data. I then reinstalled version 150, but now I'm having profile issues again. I can access and launch my old profile through about:profiles, but I can't seem to save it directly as the default profile. I don't want to have to repeat this process every time I restart the browser. Is there a way to transfer all my data (bookmarks, saved passwords, add-ons, settings, etc.) to a new profile that works with the current version? Or, can I downgrade my profile so that ESR can read it? I have tried copying the files from %APPDATA%\Mozilla\Firefox\Profiles, but it didn't work after many attempts. Please help me. I really don't want to set everything up from scratch again. Thank you!

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 have my personal account with my personal email setup in both my home PC and laptop. I want to setup a new user profile linked to a work email to hold those passwords and bookmarks separately, and be able to sync it when using my laptop as well. I would also like to be able to have both accounts open at the same time in different windows (i.e. a "work window" with the work account, and a "personal window" with my personal account)

Is this possible? How would I go about it? I looked around the about:profiles tab, but that seems to only configure profiles for my already logged in account (the personal one). I think that what I should do is create a new firefox account with my work email and give that account a profile, but I don't know if I can be logged in to 2 accounts at the same time, and I'm not sure Firefox will show me both profiles at startup, or only the ones linked to the currently logged in account. I haven't tried this because I'm unsure if I could lose my currently open tabs.

I imported my profiles from another machine to a new laptop. Now the profiles all work and I can launch into them using the shortcuts with -p "[name]" this now brings up the old wizard rather than launching directly into the profile, and the new profile manager does not see them at all.

about:profiles sees them properly.

The profiles were imported by using about:profiles to make new black profiles, then copying in the data as from the support article: http://mzl.la/1xKrFsk

Many thanks in advance for the help.

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.

MacOS 15.5

I accidentally deleted my Firefox profile not knowing its criticality. When trying to open Firefox, I receive "Profile Missing. You're Firefox profile cannot be loaded. It may be missing or inaccessible.".

1. I have uninstalled and reinstalled Firefox to no success 2. In the Library/Application Support directory, there is no Firefox or Mozilla folder 3. In the Library/Caches directory, there is no Firefox or Mozilla folder 4. I have tried opening Firefox by pressing option + click, no change in behaviour

Hi, I'm running FF 149.0 (64-bit) on Windows 11. I've used profiles for a while now and on several occassions I've "lost profiles". Currently I have three profiles which I set up and edited the icon and colour associated with each. When I launch FF I see the Profile Manager and can select any of the three and I can create a new profile which shows here. However, once in any one of the FF profiles I don't see the others - by which I mean that when I go via the hamburger lines top right and click on the current profile, the 'other profiles' section is blank. I also cannot edit the profile from using the edit pencil top right (after clicking the hamburger lines and clicking on the current profile), it takes me to about:editprofile but the page is completely blank. Confusingly, if I go to about:profiles I see two profiles, neither of which shows up in the Profile Manager! I'm going round in circles trying to understand where to edit my exisitng profiles and make sense of the five profiles that don't all show up in the same place!

I found there're several folders at my "%APPDATA%\Mozilla\Firefox\Profiles", but only one of them works on Firefox. I also checked "about:profiles", but there's only one that is running. And I can't find where to load other profiles.

What happened is that - my PC crashed, after reboot, I found Firefox became a new one. I went to "%APPDATA%\Mozilla\Firefox\Profiles", and luckily found old data still exist safely. But I went to "about:profiles", there's only a new profile. And I don't know how to load the old profile.

So I tried copying files from other profile folder, and paste to replace (or overwrite) the profile that is working. IT WORKS. The new profile is replaced by the old. But it's not a regular way to do so. How to load a profile fold?

Hello,

I've been using the profile manager, and wanted to delete a profile that i have made. However, when i select the option to delete it, it only opens up a new tab in the profile called "about:deleteprofile', which displays an empty page and does nothing. Then, I would try to delete the profile manually, in the profiles folder, but if I opened firefox or restarted my computer, it would just come back. I have attatched the relevant images below.

Just this week I found it was impossible to get to firefox browsing until I chose an upsetting blob as my profile. Is there anyway to skip this step or at least to change that blob to something that makes a more pleasant experience?

Just this week firefox has been demanding that I choose a profile before I gain access. Can I skip this step? And how can I change the unpleasant blob that I must choose. I have got one answer which requests a screen shot but I can't find my question to attach it. (I can't find the old search questions--but I'm most elderly.) and need links or reminders. Anyway, I'll put the screen shot here.

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 have a question about deleting a Firefox profile. When I access the profile screen via "about:profiles," I see two profiles: "default-release" and "Default User." The "default-release" profile is fine because it displays the message "This is the active profile and cannot be deleted." But is it okay to delete the "Default User" profile? Should I also delete the files in the root directory of the C: drive and the local directory? If I delete the "Default User", will it be deleted as well?

Hello, When I went to launch Firefox after starting up my PC this morning, I was greeted with: "Your Firefox profile cannot be loaded. It may be missing or inaccessible".

I went right to the Mozilla forums and found the help page [https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing...] . In this article it detailed how I should go into my AppData, then Mozilla, then Firefox, and look to see where my profile.ini file is. My profile.ini file was there, alongside the installs.ini and a few other folders. I attempted also to launch the profile manager using run and the "firefox.exe -P" command, but I got the same profile error as when I tried launching the app. The help page then recommended deleting the profile.ini file and then launching Firefox to hopefully remake the default profiles.ini file and enable me to launch Firefox, so I attempted that. When I tried relaunching Firefox, the profiles.ini file did not re-appear in my Firefox folder.

I then tried deleting the Firefox folder itself, and relaunching Firefox. This resulted in it being remade, but with just 2 folders left: Crash Reports and Pending Pings. Obviously that's not ideal, so I right clicked the Firefox folder and used the Windows "Previous versions" feature to restore the Firefox folder to a backup of how it was this morning. I then re-tried launching and I still got the same missing profiles error message. I also briefly attempted manually making a new profiles.ini file with notepad, and pointing it towards my Profile withing my Profiles folder, but that still resulted in the same missing profiles error.

This is basically where I am at now. I have confirmed that I do in fact see my actual profile in my "C:\Users\****\AppData\Roaming\Mozilla\Firefox\Profiles" folder, and as far as I can tell my profiles.ini file correctly points towards it. I did another reset of my Firefox folder to a backup of where I was at this morning before attempting anything. I can confirm my Windows account (Admin, and only account on the computer) has full read and write access to all Folders and files within the Mozilla folder, although I will mention some of the files in the Firefox folder were marked with the "Read-Only" attribute (not sure if that matters, but I tried unchecking those and still no luck)

As far as I can tell I have thoroughly exhausted all the easily accessible tips on the internet for solving this, so I am wondering what to try next?

TLDR: Error: Your Firefox profile cannot be loaded. It may be missing or inaccessible" Already Attempted (And failed): -deleting and prompting a remake of the profiles.ini folder -using firefox.exe -P to launch Profile manager -deleting Firefox folder to prompt a remake of that -multiple uninstalls and reinstalls of Firefox -manually remaking profiles.ini file after it didn't come back after deletion

Will link images of (1) profiles.ini file. (2) Profiles folder.

bold text Firefox has been my browser forever. When I tried to open it this morning I was invited to create a profile, so no profile, no Firefox..... I've never had to do this before and am reluctant because of the apparent threat of losing all my passwords and bookmarks. I'm 85 years of age so don't need this complication. Any help would be appreciated, complicated high tech answer will probably be beyond me. Brian.

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