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How do I recover my old browser session and its open tabs on mac? "Restore my previous session" wasn't an option, and I already tried deleting the sessionstore* files in Finder

  • 3 replies
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  • Last reply by cor-el

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This same issue happened a couple years ago, but I'm hoping it's possible to go another level deeper. Here was the answer I received, which I already attempted, but unfortunately it did not work this time:

"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.

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."

Then I replied with the following:

i actually found the file in "sessionstore-backups" folder named "previous.jsonlz4" and realized it was my last session based on the date and time in the file info (when i last shut off my computer when firefox crashed).

i then copy & pasted that file into the main/master folder named "jwlxf24d.default". i then deleted the file named "sessionstore.jsonlz4" in that main folder, and renamed the copy & pasted file to the same one i just deleted: "sessionstore.jsonlz4".

this was the only file i needed to delete in order for my old tabs to reload.

so i then restarted firefox, and all of my old tabs loaded!"

+++++

So, are there any other techniques to recover my tabs from an old session? After searching in the Firefox Profiles Folder in Finder, and organizing the files by the "Date Created" column, I did locate some .jsonlz4 files with the date/time from my old session that I'm hoping to recover..... but I tried the same technique mentioned above in my old reply, and it didn't work.

Is there any way to work with the following files, or other ones, that have the same date as the session I'm hoping to recover?.... xxxxx.main.jsonlz4 xxxxx.event.jsonlz4 These are located in the following folders: jwlxf24d.default > datareporting > archived > 2022-03

There were no .jsonlz4 files with the correct date located in the "sessionstore-backups" folder, which is what I was able to work with in the past. Really hoping there's another way to solve this issue.

This same issue happened a couple years ago, but I'm hoping it's possible to go another level deeper. Here was the answer I received, which I already attempted, but unfortunately it did not work this time: "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'''. 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." ''Then I replied with the following:'' i actually found the file in "sessionstore-backups" folder named "previous.jsonlz4" and realized it was my last session based on the date and time in the file info (when i last shut off my computer when firefox crashed). i then copy & pasted that file into the main/master folder named "jwlxf24d.default". i then deleted the file named "sessionstore.jsonlz4" in that main folder, and renamed the copy & pasted file to the same one i just deleted: "sessionstore.jsonlz4". this was the only file i needed to delete in order for my old tabs to reload. so i then restarted firefox, and all of my old tabs loaded!" +++++ So, are there any other techniques to recover my tabs from an old session? After searching in the Firefox '''Profiles Folder''' in Finder, and organizing the files by the "Date Created" column, I did locate some .jsonlz4 files with the date/time from my old session that I'm hoping to recover..... but I tried the same technique mentioned above in my old reply, and it didn't work. Is there any way to work with the following files, or other ones, that have the same date as the session I'm hoping to recover?.... xxxxx.main.jsonlz4 xxxxx.event.jsonlz4 These are located in the following folders: jwlxf24d.default > datareporting > archived > 2022-03 There were no .jsonlz4 files with the correct date located in the "sessionstore-backups" folder, which is what I was able to work with in the past. Really hoping there's another way to solve this issue.

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.....or maybe there's a backup to the sessionstore-backups folder that lives somewhere else, where there would be an archival folder with only "previous.jsonlz4" files (previous sessions), and I could find the specific date of a previous browser session? Kind of similar to a browser history that displays months worth of tabs, but in browser session format.

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Sorry, but can you "undelete" those files right now so you can use them for session recovery? You can copy them to a safe location so Firefox doesn't overwrite them immediately.

If you get them back, I have a tool to preview their contents. Drag and drop a recently updated file onto the box on my page, then click Scrounge URLs:

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

If you don't get a list within 15 seconds, that probably means the script is caught in a loop. You may need to close the tab to avoid a tab crash and then try again in a new tab.

If you get a useful list, use the Save List button to archive it as a web page of clickable links for future reference, in case no other approach is successful.

(Data Reporting isn't related to session history, so you can ignore those files.)

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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