This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

How to restore a backed up session?

  • 7 replies
  • 1 has this problem
  • 9 views
  • Last reply by MartyJames

more options

I've recently been working across three different windows of tabs. Each time I restarted Firefox I would go to "History > Recently Closed Windows" and bring up the other two windows.

However, I accidentally opened a couple of pop-up windows, which meant that the windows I'd been working on were no longer in the History menu.

I immediately backed up my entire Profile folder (including the sessionstore-backups folder).

So now I would simply like to know how do I restore from a backed up session? I would have thought this information would be all over the internet, but I've just spent ages searching for it and cannot find it anywhere. I read a few articles on this site but I found them really over-complicated and confusing.

I just want to know how to restore backed up sessions.

I'm surprised there's no option to do it in the History menu.

I've recently been working across three different windows of tabs. Each time I restarted Firefox I would go to "History > Recently Closed Windows" and bring up the other two windows. However, I accidentally opened a couple of pop-up windows, which meant that the windows I'd been working on were no longer in the History menu. I immediately backed up my entire Profile folder (including the sessionstore-backups folder). So now I would simply like to know how do I restore from a backed up session? I would have thought this information would be all over the internet, but I've just spent ages searching for it and cannot find it anywhere. I read a few articles on this site but I found them really over-complicated and confusing. I just want to know how to restore backed up sessions. I'm surprised there's no option to do it in the History menu.

Chosen solution

Here's the solution, thanks to the help of McCoy and cor-el:

  1. Make sure Firefox is closed (copy these instructions if necessary).
  2. Just in case, make a backup copy of your whole profile folder
  3. In your profile folder, go into the sub-folder called sessionstore-backups - this is where Firefox keeps backups of the tab and window sessions
  4. Order the files by date, and find one that best matches the date and time you want to restore from
  5. The file may be titled previous or recover or upgrade. That doesn't matter, as long as the file extension is .jsonlz4
  6. Make a copy of this file and rename it to sessionstore.jsonlz4 - it's important to keep the file extension the same
  7. Copy this file into your main profile folder.
  8. Start Firefox and your session will be restored to the session from the backup you chose.

If you're like me, you'll find it confusing that this process ADDS a new file to the profile folder, but does not actually REPLACE any files. I'm not sure how session information can be replaced when no file is replaced? But it seems to work.

It also seems confusing why this process is so complicated, seemingly undocumented, and you can't just do it from the Firefox History menu. But that's another issue I guess :)

Read this answer in context 👍 0

All Replies (7)

more options

Hello MartyJames,

I'd like to ask you if what has been suggested in this thread would help :

https://support.mozilla.org/en-US/questions/1250064

But chances are that I totally misconstrued your question ..... (?)

more options

McCoy said

I'd like to ask you if what has been suggested in this thread would help : https://support.mozilla.org/en-US/questions/1250064

Hi again McCoy :)

Yes, I had read that thread (and several others) but didn't find it helpful. The answers given on that thread concern:

• "history manager" • "preserving the jsonlz4 file extension" • "the scrounger.html tool"

I'm afraid none of the above things mean anything to me, and don't sound like solutions to my problem.

I am simply trying to figure out how to restore my closed window history from backup.

Specifically I would like to know:

1. Which file (in my profile folder) contains data for the previously closed windows? - Whatever file it is, I guess I should try replacing it with its counterpart from the backup copy I made yesterday.

2. Also, does Firefox back up this data? Is it contained somewhere in the "sessionstore-backups" folder? There are all sorts of different files in there and I wouldn't have a clue which one was the right one, or what to rename it to and where to put it.

To put it simply... What does someone do when he loses his session/tabs/windows data and wants to restore it?

Modified by MartyJames

more options

Confession :

As the thread I linked to, is your own thread from less than two months ago; I thought that maybe you had forgotten all about posting it ......

I really can't come up with any other possible solution, but I'm sure that someone else will come to your rescue (sorry .... ).

more options

McCoy said

As the thread I linked to, is your own thread from less than two months ago; I thought that maybe you had forgotten all about posting it ......

LOL that is hilarious! I'd read that thread twice today and didn't noticed that the OP was I!

Yes, I had completely forgotten about that thread. I can be forgetful at times. It seems your memory is excellent though!

Sorry to start two similar threads in a short space of time.

In the end, I worked around that problem by just looking at my history and figuring out what the missing tabs were. It saved me from having to delve into the workings of Firefox's files, which I hate having to touch. I had really got fed up of messing around with them and not getting anywhere.

I have just read that thread again and tried re-doing what I did before, only this time I used cor-el's advice.

To my surprise - it worked! :)

It was a shock, because it really didn't seem like it would work. The trick was to not change the file extension, so you're basically adding a brand new file into the profile folder which never existed before. To me, that doesn't seem to make any sense. But it works.

For the benefit of others who search this question, I'm now going to give a concise answer to my own question in a separate post…

more options

Chosen Solution

Here's the solution, thanks to the help of McCoy and cor-el:

  1. Make sure Firefox is closed (copy these instructions if necessary).
  2. Just in case, make a backup copy of your whole profile folder
  3. In your profile folder, go into the sub-folder called sessionstore-backups - this is where Firefox keeps backups of the tab and window sessions
  4. Order the files by date, and find one that best matches the date and time you want to restore from
  5. The file may be titled previous or recover or upgrade. That doesn't matter, as long as the file extension is .jsonlz4
  6. Make a copy of this file and rename it to sessionstore.jsonlz4 - it's important to keep the file extension the same
  7. Copy this file into your main profile folder.
  8. Start Firefox and your session will be restored to the session from the backup you chose.

If you're like me, you'll find it confusing that this process ADDS a new file to the profile folder, but does not actually REPLACE any files. I'm not sure how session information can be replaced when no file is replaced? But it seems to work.

It also seems confusing why this process is so complicated, seemingly undocumented, and you can't just do it from the Firefox History menu. But that's another issue I guess :)

Modified by MartyJames

more options

I knew that you would figure it out  !

All you had to do is to get back to that thread, give it another try and surprise yourself ....

Well done, you  !

All you have to do now is to mark your last post as Chosen Solution and then lean back and relax.

more options

McCoy said

I knew that you would figure it out  ! All you had to do is to get back to that thread, give it another try and surprise yourself .... Well done, you  !

LOL that's very kind of you dear :)

Given my terrible memory, I'll be back here soon reading my own solution again!

Thanks again McCoy! :)