Firefox Community Forum

I deleted a profile not knowing it would delete everything I had. How can I undo it? I didn't want Firefox Profiles, it was forced. I deleted it, and everything just got deleted. Can someone please help revert this? Thanks.

I have enabled the option to open the previous windows and tabs. I had one window that I always closed last as it had a lot of groups that are important for my work, so it used to open every time I started Firefox. Sometimes, even if I closed the window by mistake without closing other windows, I was able to get it back by pressing ctrl+shift+n.

But yesterday, I might have closed it by mistake and when I pressed ctrl+shift+n , it didn't come back. I wasn't able to access my window and now it's all gone. I don't see anything in recently closed windows in history.

I need those tabs back as they are very important for my work. they were a lot of tabs. I had many groups but now all are gone. I tried by using the previous.jsonlz4 in the sessionstore-backup by renaming it in the default-release profile as sesstionstore.jsonlz4 but still wasn't able to access my window.

I didn't clear my history as the tabs opened in the window still show up in the history.

Kindly help as soon as possible

My computer ran into an error and restarted and I lost my entire browsing history, bookmarks, extensions, etc. Now I have nothing saved and the only browsing history my computer is showing is when I briefly opened microsoft edge. I regularly used duckduckgo, so most of my data is gone. Is there anything that can be done or is it just gone.

Last night I had an operating system update. Before the OS update, I closed all open apps, including Firefox. In the past, the session I closed the previous evening was restored. But this morning, all my pinned tabs and other open tabs are gone, and Restore Previous Session does not appear as an option on the dropdown menu. Recently Closed Tabs is pretty random, not really helpful. Recently Closed Windows only shows one tab that I opened this morning (probably a mistake on my part). Is there any way for me to retrieve the session from yesterday?

Mozillers,

I depend heavily in my environmental and other work on Firefox and am grateful for its ability to restore previous tabs when my laptop, not infrequently, stops working abruptly.

Now the much-used bookmarks have disappeared. A search site states promisingly:

"To restore Firefox bookmarks, use the built-in backup feature by going to Menu > Bookmarks > Manage Bookmarks > Import & Backup > Restore, then select a dated backup or a manual file (like a JSON backup) to bring back lost bookmarks..."

But my Firefox's Bookmarks drop-down menu has no Manage Bookmarks option. PLEASE, what must I do?

Elsewhere I managed to find this file which apparently contains recent bookmarks:

"C:\Users\User\AppData\Roaming\Mozilla\Firefox\Profiles\unk14jlv.default-release-1647366062305\bookmarkbackups\bookmarks-2025-12-26_95_4IdGtYxezJpwuH1UIiT1bRwe1K6bcGO8rv0mqa9rUWU=.jsonlz4"

But attempting to open it with Applications\firefox.exe (default) accomplishes nothing.

FOOL-proof instructions would be wonderful. Thank you.

I have been using old-style profiles for a long time, but they didn't work so well for me. The new profiles system was great - specifically that each one was a FF instance that could be opened and quit independently of any others (and most importantly had a different icon). I setup 5 or 6.

But i quit all my FFs due to memory issues. Then after restarting a FF, it was an instance from the old profiles system and there was no profiles item in main menu (under three horiz lines top-right).

Going to about:profiles didn't show them (as expected).

I started from command-line to launch FF with Profile Manager and after selecting a profile that way, then there now a Profiles menu item. However it empty.

I had a look and there is a ` ~/Library/Application Support/Firefox/Profile Groups` that contains a number of sqlite files and each has a -shm and -wal file also. I looked in the profiles table for each of these. 1 lists all the new profiles I created and one points to default old-style Profile instance that opens (ie. Profiles/Main-Firefox-Window).

about:config - browser.profiles.enabled is true

I also noticed a browser.profiles.forceEnableRefresh but it appears to be undocumented.

My question: HOW can I restore my new profiles? I put some work into icons etc.. and of course their history, so i don't want to have to recreate them.

Hello there, today was released a new version of firefox. downloading it not only crashed my computer, it also removed all my history and bookmarks. is there any way to revert this?

I updated Firefox to 145.0 this morning, and after Firefox had restarted, it had lost all bookmarks and the bookmarks toolbar. I have spent all day following links to correct the problem and got nowhere. I have restarted Windows and Firefox countless times - no change. I've even tried reinstalling Firefox over the existing version. If I go to bookmarks > manage bookmarks > restore and backup, sometimes that will load, others not. When it does load, it fails to find a file to restore from. 10 years of bookmarks, links & research vanished.

Can someone please provide a solution (preferably in Layman's terms) to this??

version 141.0.3 on a 2019 iMac 11.7.10 ... when this version was downloaded, bookmarks and history disappeared. Is there a way to recover or do I have to begin from scratch ?

Hi

I've just booted my machine and opened Firefox, only to be presented with a completely fresh install.

All my settings, bookmarks and history gone. It was fine yesterday when I closed it and powered down.

I'm running Kubuntu, I've checked the .mozilla folder and nothing...it's like my profile has just been overwritten.

Not happy at all, I'm starting to dislike Firefox.

Can anyone offer any help or advice please?

Thanks in advance.

All my bookmarks disappeared and the bookmark button does not work. I have refreshed Firefox - no change. I have uninstalled and reinstalled Firefox but still no restoration of Bookmark button functionality. OS Win10

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, I'll try to explain exhaustively my problem and what I've tried.

While looking at adding a new profile, I made a mistake and deleted the actual profile. Firefox immediately shut, and I made the mistake to open it right after...

It started from zero, as it had no profile to go into. Creating a new profile in the same time. I did this a few time, nothing changed obviously. I went to the AppData/Roaming path to find my old profile, which wasn't there anymore. I then managed to recover my profile files thanks to Recuva and EaseUS.

But now, I'm stuck. When adding the files in the newly created profile, it seems to roll back to the profile creation prompt (like import stuff from other browsers etc.). Copy/pasting only the desired sessionstore or the previous backup doesn't work either. It also tried to put the "good profile" in the Profiles folder. Firefox didn't recognize it, and I couldn't create a new profile from this folder in the Profile Manager as it said "this name is already used" etc. (it's a default-release) I then tried to edit the profiles.ini and install.ini to force Firefox on the wanted profile. Which succeeded and failed at the same time: it opened the right profile-folder, but without any session, bookmark... and back again to the profile creation prompt. And created a new empty sessionstore, prefs, etc.

Then I'm left with my recovered backup files and no idea how to import them...

Any help will be warmly welcomed! Cheers

Hi, I recently purchased a new laptop and want to bring over the bookmarks I had from my old laptop. I had copied what I thought was the profile from the old one and copied it into the new laptop - but I'm not sure of the next steps :(.