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

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

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

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.

I don't understand how this might help me recover my tabs, if you could explain, thanks.

Did you check the content of those recovery files to verify they aren't corrupted ?

You can look at this tool to inspect a compressed sessionstore file.

• https://www.jeffersonscher.com/res/scrounger.html

You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.jsonlz4 to replace the current file with Firefox closed.

• make sure to backup the current sessionstore.jsonlz4

Did you check the content of those recovery files to verify they aren't corrupted ? You can look at this tool to inspect a compressed sessionstore file.

• https://www.jeffersonscher.com/res/scrounger.html

You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.jsonlz4 to replace the current file with Firefox closed.

• make sure to backup the current sessionstore.jsonlz4

I tried it with the files I recovered with ShadowExplorer recovery.baklz4 recovery.jsonlz4

But it doesn't work, and the tool of Jefferson doesn't say anything about those two files, am I doomed?

Did you check the content of those recovery files to verify they aren't corrupted ? You can look at this tool to inspect a compressed sessionstore file.

• https://www.jeffersonscher.com/res/scrounger.html

You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.jsonlz4 to replace the current file with Firefox closed.

• make sure to backup the current sessionstore.jsonlz4

I already tried to check the content of recovery.baklz4 and recovery.jsonlz4 that I got thanks to ShadowExplorer with that tool, but it doesn't show me anything, is it over for me?

If the tool isn't able to show any labs listed in the recovery files then that route to a solution is blocked.

What files do you have in the sessionstore-backups folder ?

Is there a recent upgrade file you could use ?

You will normally find these files in the sessionstore-backups folder:

• previous.jsonlz4 (cleanBackup: copy of sessionstore.jsonlz4 from previous session that was loaded successfully)
• recovery.jsonlz4 (latest version of sessionstore.jsonlz4 written during runtime)
• recovery.baklz4 (previous version of sessionstore.jsonlz4 written during runtime)
• upgrade.jsonlz4-<build_id> (backup created during an upgrade of Firefox)

You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.jsonlz4 to replace the current file with Firefox closed.

• make sure to backup the current sessionstore.jsonlz4

If the tool isn't able to show any labs listed in the recovery files then that route to a solution is blocked. What files do you have in the sessionstore-backups folder ? Is there a recent upgrade file you could use ? You will normally find these files in the sessionstore-backups folder:

• previous.jsonlz4 (cleanBackup: copy of sessionstore.jsonlz4 from previous session that was loaded successfully)
• recovery.jsonlz4 (latest version of sessionstore.jsonlz4 written during runtime)
• recovery.baklz4 (previous version of sessionstore.jsonlz4 written during runtime)
• upgrade.jsonlz4-<build_id> (backup created during an upgrade of Firefox)

You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.jsonlz4 to replace the current file with Firefox closed.

• make sure to backup the current sessionstore.jsonlz4

Nothing exploitable it seems.

"previous.jsonlz4" is from today, it seems that it rewrited the moment I opened the bugged session of Firefox. "recovery.jsonlz4" and "recovery.baklz4" are from today too. For "upgrade.jsonlz4-<build_id>" I have one of 2021, probably the old session that opened instead of my current one, and two from today.

Is there any solution besides Firefox workarounds? Something with Windows restoration system, or another software like ShadowExplorer? At this point I'm open to everything to be honest...

Firefox has been upgrading at least twice a month, but your Firefox identified itself as version 92, so it sounds as though you have skipped many updates over the past six months. Does that sound right or is it possible your Firefox did some kind of rollback?

Firefox has been upgrading at least twice a month, but your Firefox identified itself as version 92, so it sounds as though you have skipped many updates over the past six months. Does that sound right or is it possible your Firefox did some kind of rollback?

I only skip updates for a week or two, waiting for them to be stable. It's really weird

Is it possible that you have multiple Firefox installations? The two most common locations are:

• C:\Program Files\Mozilla Firefox
• C:\Program Files (x86)\Mozilla Firefox

Is it possible that you have multiple Firefox installations? The two most common locations are:

• C:\Program Files\Mozilla Firefox
• C:\Program Files (x86)\Mozilla Firefox

Mozilla Firefox is in Program Files but Mozilla Maintenance Service is in Program Files (x86)

Okay, that's fine. Can you check whether your Firefox has updated back to the current release by now?

Update Firefox to the latest release

By the way, the reason I'm suggesting that is so you can explore this page (the Launch part won't work if you open a newer profile with an older version):

Profile Manager Page

Inside Firefox, type or paste about:profiles in the address bar and press Enter/Return to load it.

This page should list at least one profile and could list many. (Each profile has two folders and one or more buttons. Do not use any Remove buttons!)

The profile that Firefox is currently using will have this:

This is the profile in use and it cannot be deleted.

Do you have any other profile(s) listed on this page? If so, you can check whether it is the one you were using recently by clicking its Launch profile in new browser button.

If it isn't what you want, simply close that new window.

If it IS what you want, back on the about:profiles page, click the Set as default profile button for that profile so Firefox uses it automatically at the next startup.

Any luck?

Okay, that's fine. Can you check whether your Firefox has updated back to the current release by now? Update Firefox to the latest release

By the way, the reason I'm suggesting that is so you can explore this page (the Launch part won't work if you open a newer profile with an older version): Profile Manager Page Inside Firefox, type or paste about:profiles in the address bar and press Enter/Return to load it. This page should list at least one profile and could list many. (Each profile has two folders and one or more buttons. Do not use any Remove buttons!) The profile that Firefox is currently using will have this: This is the profile in use and it cannot be deleted. Do you have any other profile(s) listed on this page? If so, you can check whether it is the one you were using recently by clicking its Launch profile in new browser button. If it isn't what you want, simply close that new window. If it IS what you want, back on the about:profiles page, click the Set as default profile button for that profile so Firefox uses it automatically at the next startup. Any luck?

No luck, sadly, I only have one profile