Firefox Community Forum

FireFox browser closed and when I opened it all my bookmarks are gone, all of my history is gone everything is gone as though I never ever used firefox in my life.

I posted a question in here two days ago because my firefox wouldnt open anymore i got a follow up answer telling me to give the crash id but never got a follow up after i sent it . i tried shuffling between profiles and in the end got it working but today my pc had a crash while firefox was open and it had to restart when i tried to open firefox its as if i just installed it and i dont have any backups to be honest i tried checking the appdata folder and there is a profile folder that seems big enough that it might be mine but it doesnt seem like firefox is reading it for some reason i tried switching the data in the profile folder that firefox is considering but it didnt work .

• Old laptop can no longer access the internet; corrupt Windows 10. Bought a new HP laptop. Have Sync turned on on both laptops but am not getting any favorites, passwords that I desperately need. What are my options given the old laptop can't connect.

Something very bad happened to me today (11/3)....

Firefox 144.0.2 was installed on 10/30/25, and everything has been fine until today. I don't know why or how, but ALL of my OPEN tabs (of which I have many--and have it fixed so they always re-open when Firefox starts), ALL went away.

In reading conventional steps to recover such from sessionstore-backups, those instructions sounded straightforward. However, even though ALL FIREFOX PROCESSES were ended, I could not copy the contents of the sessionstore-backups folder nor could I delete anything--EVEN THOUGH I am the owner.

Even after providing Admin perms.

I could get rid of profiles.ini, which initially proved diasterous, because then Firefox thought I was brand new, so ALL of my passwords saved through Firefox these many years, went "poof".

Fortunately, I was able to get that back, but I still cannot get all of my tabs back, and conventional instructions to do so aren't working.

After recovering from my heart attack for initially losing my passwords, I am breathing a little better right now, but it sure would be nice to get all of my open tabs back again. I don't know why I am not able to manipulate the files within sessionstore-backups. I think if I could eliminate the files in that folder EXCEPT for upgrade.jsonlz4-20251027123126, which possesses a 10/29/25 date, these should be the open tabs just before the 144.0.2 installation, and all should be right with the world, once more.

I have performed/examined many steps offered under this category, but most assume I can copy them elsewhere for safe-keeping and/or removing all but the one I want Firefox to "use". Because something is preventing me from doing this, though, I am being stymied in what ought to be the solution. As a test, I was able to copy files from a much older profile--so I can prove the basic steps SHOULD HAVE worked. Unfortunately, I cannot do the same with THE (more recent) folder in question. I can't get rid of parent.lock, either (and I have ensured no Firefox processes are running via Task Manager).

Repeatedly.

Something else is at work, here. Any help or assistance from community experts would be most helpful.

Thanks very much in advance.

-MG

Dear Mozilla Support,

My name is Sizhe Xiong. Today when I launched Firefox on my Windows computer, the browser suddenly required me to select or create a new profile before continuing. I had no option to skip this step, so I created a new one.

After that, Firefox asked me to log in or register a Mozilla account. I used the same Gmail address that I’ve always used for Firefox Sync, but it seems that a new account was automatically created, and all my previous data — including bookmarks, history, saved passwords, and extensions — disappeared.

When I checked my local Profiles folder under C:\Users\<username>\AppData\Roaming\Mozilla\Firefox\Profiles, I found several new folders created around the same time, but none of them contain my old data (all places.sqlite files are around 5120 KB).

These bookmarks and passwords are very important to me. Could you please help check if it’s possible to recover my old Firefox data, or if my previous Sync data can still be linked to my Mozilla account (using the same Gmail address)?

Thank you very much for your help.

Best regards, Sizhe Xiong

Hi, All of a sudden, I lost absolutely all of my bookmarks. My PC is running Windows 11. My Firefox account was and still is logged in. At first, I thought the data loss was due to a CCleaner cleanup using their latest update. After the data was lost, I tried running another CCleaner cleanup, but this time it didn’t delete the bookmarks. So I honestly have no idea how this could have happened. These were bookmarks I had saved over many years... It’s a disaster.

PLZ Help

Hello and good afternoon. I have a problem with my last session as it doesn't appear, even when I try to do it manually in Settings-History-Import and backup-Restore, it shows me some options of different dates with all my last browser history, but none of them works, it simply doesn't open any of the web pages. I don't have any other profile, and I already tried the troubleshooting too I Hope you can help me. Thanks in advance

I think that this recent update removed all of my tabs and tab windows, it has done this before and I don't understand why, I have the old update session file still (The 11/11/2025 One) and I tried to use that one to bring the tabs back by putting the file in the sessionstore-backup folder with no other file in it, but they didn't come back. I am genuinely confused as to why it doesn't work, I have renamed and deleted sessionstore.jsonzl4 files but it still comes up as a new session.

Mozilla usually doesn’t restore all the windows I’m working in; when I open it, it only restores a few of them. I usually use the ‘History’ > ‘Recently Closed’ > ‘Reopen All Windows’ option, but this time not all the windows I need are being restored. My most important window, containing 1,000 essential tabs for various articles, hasn’t been restored, and it seems as though I have absolutely no chance of finding it at all; I don’t even have a ‘Restore previous sessions’ button. I don’t know how to get that window back, because restoring the tabs one by one would take an age and I’d probably lose a lot of them (it’s very important that these were tabs, not bookmarks). What should I do?

My passwords are apparently lost today after updating Firefox.

What went wrong? How could that happen? Why, Why Why?

Anyway to get them back? Are they hidden somewhere?

Anyone else suffering from this update too?

Any help or insights as to why would be greatly appreciated.

w

I lost all my data after installation of new firefox. I have lots of important data in that profile.

I forgot the password to sign in and when I reset, a new profile was created for me and all my data are gone.

Now, I even know the original password. I did not know, I will lose my data. How can I get my data back? Please help.

Can Firefox do anything to recover all of the downloads I'd saved until I accidentally had CCleaner erase everything? I don't know what else was deleted, but getting them back would be a big help.

Hello,

This morning Firefox stopped loading new tabs, which usually means it is due for an update and restart. On my work computer, updates are managed by my organization, so I cannot prompt it to check for updates directly, but rather can just restart the application and it updates once closed. Today when I closed the window then clicked the shortcut to reopen, it notified me the exe file had been removed and prompted me to open the Windows store and reinstall, which I did. I have no indication as to why it uninstalled. All of my bookmarks and other history appear to have been wiped.

I have been trying on the support site to see if this data is recoverable, but nothing has panned out so far.

I have used Firefox as my primary browser for almost twenty years and frequently encourage friends and family to use it if they don't already. I have never experienced anything like this before. I am hopeful somebody will be able to assist me where reading through support center options hasn't yet, but if this is not resolvable, I'm done- the crash helpfully wiped everything clean, after all.

Any suggestions or response is greatly appreciated. Best, Z

I AM HAVING THE SAME PROBLEM AGAIN, I HATE HAVING EVERY SINGLE ONE OF MY TABS DISAPPEAR WHENEVER IT CLOSES WEIRDLY AND I LITERALLY CANT RECOVER ANYTHING, AND IT GIVES ME SOMETHING NEW, WHAT THE HELL EVEN IS THIS FIRST FILE, I HAVE NEVER GOTTEN THAT JSONLZ4 FILE E V E R!!! AND WHEN I TRIED TO DO THE SAME METHOD OF REPLACING THE FILES WITH ONE OF THE OLD RECOVERY FILES LIKE IN MY OLD QUESTION, IT DOESNT FUCKING WORK, SORRY TO SWEAR BUT ITS UTTERLY RIDICULOUS DUDE!!!

I'm running the current version (144.0, 64-bit) on a Dell Inspiron laptop. Just now, I tried to save a bookmark, but I found that a goodly number (not all) of my bookmark folders had disappeared. When I tried to restore from a Firefox backup, I got an "Unable to process file" message. What's wrong , how do I fix it, and how do I get the missing bookmarks back?

Windows 11 Firefox crashed on opening continuously so unable to safe open etc. Did update intel graphics to no avail. Uninstalled in add programs in settings. Did not choose to delete data. Reinstalled and now can't find my profile.

So far hate new Firefox that I have been forced to switch to - very annoying and such a waste of my time trying to sort out my bookmarks. May make me switch to Edge or something.

Followed the instructions - C:\Users\name\AppData\Roaming\Mozilla\Firefox\Profiles\ - found a backup but no information as to how to get the bookmarks into the new Firefox?????

Many of us are older users and perhaps not so savvy as to how to do this.

And so it would have been nice if Firefox could have been more "nice and be specific" with this forced change over.

Thank you

I am changing from Win 11 to Linux Mint and want to use as much of my Win Ff profile there... What can I trnansfert, and how, where will I find Ff extensions for Linux?

Thank you

I read the existing articles and followed them, starting with "manage bookmarks". When I click on restore, there is a list of the last 15 backups by date. EVERY one of them results in an error message "unable to process the file".

Manually searching for bookmarks.html or json, resulted in nothing found at first. Then I discovered the path to the bookmarks folder were all hidden folders (after the 'user' folder). I got them to display in file explorer ('show hidden files' selected) and tried to manually select the JSON files that way, to restore bookmarks. That also did not work, resulting in the same message depicted below.

Please help