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 can I make Firefox restore my previous session after it fails to do so after a normal shutdown?

more options

Hi Forum Folke!

Running version 75.0. This is the second time I've had this issue. Normal shutdown of Firefox, using the "X" in the upper right hand corner of the window. Shutdown appeared normal, no messages or hangs or anything like that... nothing out of the ordinary.

Starting Firefox up the next morning... nothing. Just a blank new tab. "Restore previous session" option is not available (doesn't show at all, not just grayed out.) I DO have "Restore previous session" checked in "Options," and 99.99% of the time it works just fine. Not this time, though! I'm getting no error messages or prompts of any kind, and Firefox has not offered to restore previous session.

I've found what appears to be the restore file in the main Profile folder (previous.jsonlz4), dated from yesterday, but apparently Firefox can't find it, or can't use it (or maybe that's not the file at all, for all I know). Is there any way to "lead Firefox by the nose" to this file? Or the 'correct' file for my last session?

Everything I had opened in tabs DOES show up in History, but I'd rather not have to sift through that whole mess to manually rebuild what Firefox should have remembered in the first place; that's why I use restore previous session.

Any suggestions would really be appreciated; nothing earthshaking, but I had a lot of open tabs, researching the purchase of a number of items that I was cross-comparing for price/availability/maker, etc, and remembering WHICH of those tabs were open when I closed isn't going to be a fun time.

I would attach troubleshooting data, but this page assures me that "This field was populated automatically." Guess we'll see!

Hi Forum Folke! Running version 75.0. This is the second time I've had this issue. Normal shutdown of Firefox, using the "X" in the upper right hand corner of the window. Shutdown appeared normal, no messages or hangs or anything like that... nothing out of the ordinary. Starting Firefox up the next morning... nothing. Just a blank new tab. "Restore previous session" option is not available (doesn't show at all, not just grayed out.) I DO have "Restore previous session" checked in "Options," and 99.99% of the time it works just fine. Not this time, though! I'm getting no error messages or prompts of any kind, and Firefox has not offered to restore previous session. I've found what appears to be the restore file in the main Profile folder (previous.jsonlz4), dated from yesterday, but apparently Firefox can't find it, or can't use it (or maybe that's not the file at all, for all I know). Is there any way to "lead Firefox by the nose" to this file? Or the 'correct' file for my last session? Everything I had opened in tabs DOES show up in History, but I'd rather not have to sift through that whole mess to manually rebuild what Firefox should have remembered in the first place; that's why I use restore previous session. Any suggestions would really be appreciated; nothing earthshaking, but I had a lot of open tabs, researching the purchase of a number of items that I was cross-comparing for price/availability/maker, etc, and remembering WHICH of those tabs were open when I closed isn't going to be a fun time. I would attach troubleshooting data, but this page assures me that "This field was populated automatically." Guess we'll see!

Valgt løsning

Thanks, Fred... I appreciate your taking the time to read and reply.

if I understand what I'm reading correctly (debatable), I can't restore the last session, just delete the corrupted restore and backup files and start over clean? Not what I was looking for...

Do they both have to be corrupt for this to happen? As in, does Firefox check first one file, and if it's no good, then checks the next file, and so on, until there's nothing left to check and it then just opens with a new tab (like it did)?? If so... what would cause this to happen?

Unless I can find an answer to this issue, I won't feel that I can trust Firefox anymore; having to bookmark all tabs so they'll be there later is kind of a hassle, and there are other browsers available that most likely don't need for me to do this. I've been with Firefox since the beginning, but if it's going to start being troublesome like this, it might be time to reconsider.

Les dette svaret i sammenhengen 👍 1

All Replies (6)

more options

You may have corrupt sessionstore [v56] sessionstore.jsonlz4 file(s). Delete all sessionstore* files and the sessionstore-backups folder.

Type about:support<enter> in the address bar.

Under the page logo on the left side, you will see Application Basics. Under this find Profile Folder. To its right press the button Show Folder. This will open your file browser to the current Firefox profile. Now Close Firefox.

Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder

Linux: Under the page logo on the left side, you will see Application Basics. Under this find Profile Directory. To its right press the button Open Directory.

Locate the above file. Then rename or delete it. Restart Firefox.


Don't delete the files if you need to rescue any data from them, just move them out of the profile folder to some location where Firefox doesn't look for them. You can try to read out their contents using this tool: https://www.jeffersonscher.com/res/scrounger.html

more options

Valgt løsning

Thanks, Fred... I appreciate your taking the time to read and reply.

if I understand what I'm reading correctly (debatable), I can't restore the last session, just delete the corrupted restore and backup files and start over clean? Not what I was looking for...

Do they both have to be corrupt for this to happen? As in, does Firefox check first one file, and if it's no good, then checks the next file, and so on, until there's nothing left to check and it then just opens with a new tab (like it did)?? If so... what would cause this to happen?

Unless I can find an answer to this issue, I won't feel that I can trust Firefox anymore; having to bookmark all tabs so they'll be there later is kind of a hassle, and there are other browsers available that most likely don't need for me to do this. I've been with Firefox since the beginning, but if it's going to start being troublesome like this, it might be time to reconsider.

more options

kharrisma said

if I understand what I'm reading correctly (debatable), I can't restore the last session, just delete the corrupted restore and backup files and start over clean? Not what I was looking for...

FredMcD said

Don't delete the files if you need to rescue any data from . . . .
more options

When you have Firefox set to restore automatically and you get a blank window, the very first thing to check is this menu (appears in 3 places):

  • "3-bar" menu button > Library > History > Recently Closed Windows
  • "Library" toolbar button > History > Recently Closed Windows
  • (menu bar) History > Recently Closed Windows

Hopefully those are not yet gone from Firefox's memory (up to 3 closed windows).

For future reference, to avoid the closed window situation, close Firefox using the menu. Either:

  • "3-bar" menu button > Exit
  • (menu bar) File > Exit

- - - -

As a backstop to the built-in feature, you could investigate session management extensions. These are the ones I'm aware of that you might check out:

Use database storage:

Use bookmark storage:

Bookmark storage is more robust in that Firefox backs it up regularly. However, having the extra data show up when you are searching your bookmarks may be annoying.

more options

By the way, if this is the first time I've replied in one of your threads, here's a tool you can use to extract the contents of a session history file like previous.jsonlz4 to a page of clickable links for archival purposes:

https://www.jeffersonscher.com/ffu/scrounger.html

- - - -

If you want Firefox to use previous.jsonlz4 in the future, you need to hide all the files it will try first. Back everything up from sessionstore-backups, and then:

(A) Exit Firefox
(B) At the main level of the profile folder, if you find sessionstore.jsonlz4 rename that with OLD: sessionstoreOLD.jsonlz4
(C) At the main level of the profile folder, if you find sessionstore.js or sessionstore.bak, those are ancient and can be deleted
(D) In the sessionstore-backups folder, if you find recovery.jsonlz4 rename that with OLD: recoveryOLD.jsonlz4
(E) In the sessionstore-backups folder, if you find recovery.baklz4 rename that with OLD: recoveryOLD.baklz4

Now at the next startup, Firefox should run down its checklist and try previous.jsonlz4 next.

more options

Thanks jscher2000,

Your extractor (I've bookmarked it) is what bailed me out of this mess. I was not aware of all the things in the "Library/History;" I've only ever used the "Library" in the toolbar as a way to access bookmarks; I thought clicking on history would just open the sidebar, where I'd have to fish out all my "lost" tabs manually. The information you provided is greatly appreciated!!