Lets see what you have in the folder in your profile folder call sessionstore-backups. see screenshots of mine Post a screenshot of you files. In the browser go to about:support the then click on the link to open your profile folder. see 3rd screenshot

this is the folder.

Here's info about the files in the folder. https://support.mozilla.org/en-US/questions/1415643 https://support.mozilla.org/en-US/questions/1449521

From the files in your screenshot. With Firefox closed, you will see a file called sessionstore.jsonlz4 in your profile folder. This is your current session that I guess is not the one you want. Just rename it to something like old_sessionstore.jsonlz4_old. Then from your sessionstore-backups folder make a copy of one of the files from the screenshot I attached. Then rename that file sessionstore.jsonlz4 and the move it into your profile folder. Then open Firefox and it should be the session from the date of 1 of those 3 files that I show from your screenshot. MAY THE SCHWARTZ BE WITH YOU!  ;-))

thanks, I tried it with previous and recovery. will go for the update one now. hopefully it would work😃

Firefox often fails to restore the session which is why I recommend you make a copy of the folder however often you want. I try to do it once a week. see screenshot

it worked. thanks a lot. the upgrade one worked

Firefox often fails to restore the session which is why I recommend you make a copy of the folder however often you want. I try to do it once a week. see screenshot

had these tabs from 5 months. this never happened. was the first time. but now I will be keeping a copy of these.

You see my last backup was from November. Let me do it now.  ;-))

sure :)

I have the same problem I lost all the tabs. I tried doing your suggestions but ít doesnt seem to be helping.

There were 3000 open tabs on 19.01.2026 and I closed the browser- normally when I do so it refreshes itself and always the open tabs are recalled and reopened. However this time it didnt work. I see that all these tabs are visible on the History Reload Section but when I click it doesnt work either. I am so desperate and dont know how to fix it

From the files in your screenshot. With Firefox closed, you will see a file called sessionstore.jsonlz4 in your profile folder. This is your current session that I guess is not the one you want. Just rename it to something like old_sessionstore.jsonlz4_old. Then from your sessionstore-backups folder make a copy of one of the files from the screenshot I attached. Then rename that file sessionstore.jsonlz4 and the move it into your profile folder. Then open Firefox and it should be the session from the date of 1 of those 3 files that I show from your screenshot. MAY THE SCHWARTZ BE WITH YOU!  ;-))

can you check where I make a mistake and help me too please

Thanks for the reply. I actually have Firefox keeping all my information for now so there is no reason it should be clearing it. My question still stands: I do not see "Restore Previous Session" in the "History" drop-down. That prevents me from restoring a recent session without going through the file name change etc. that you suggested. Why do I not have the "Restore Previous Session" as an option in "HIstory"?

That would be a dev question because this is the issue that brought me here many years ago. https://support.mozilla.org/en-US/questions/1312258#answer-1376047 Every time I ask them I get crickets...

I have the same problem I lost all the tabs. I tried doing your suggestions but ít doesnt seem to be helping. There were 3000 open tabs on 19.01.2026 and I closed the browser- normally when I do so it refreshes itself and always the open tabs are recalled and reopened. However this time it didnt work. I see that all these tabs are visible on the History Reload Section but when I click it doesnt work either. I am so desperate and dont know how to fix it

Hey Duygu,

Still need help with this issue? If so, open a new issue and send me an email via this forum. You also need to show the files in a detailed view so we can see the size of the files. There are times when a restart or update resets the files which is why I make a backup of the sessionstore-backups folder.

I'm having the same problem tried everything I could find, no luck. Recent history was there clicked on it nothing much happened, when back in and now it's not a option.

You can use the extension Tab Session Manager. It works flawlessly and will also save tabs in private browsing if you want.

@Duygu_o.z

Your first screenshot shows you left the renamed sessionstore.jsonlz4 in the sessionstore-backups folder. You need to move sessionstore.jsonlz4 to the root level of the profile folder (i.e. where you see the sessionstore-backups folder) with Firefox closed to replace the file created by Firefox.

I'll get right on that.

I had the same issue. When I used Pro 3, I closed the Firefox sessions by "x"ing out in the upper right corner and shutting down my Pro 3. I upgraded to a Pro 12 and found that by closing down my session then shutting the Pro 12 down like I did with the Pro 3 that next time I opened Firefox that all my previous tabs were gone. I had to go thru the slow process of re-establishing all my previous tabs. Last nite when I planned to shut down I exited Firefox, under the File tab and selecting Exit at the bottom of the list. This morning when I opened up Firefox, all my previous tabs were restored. Not sure if anyone else has tried this or whether this is the solution or not. Over the next few days I'll continue closing Firefox in the similar way and see whether that will solve my issue..