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restored session is missing a lot of pages - anything i can do?

  • 5 replies
  • 1 has this problem
  • 13 views
  • Last reply by teoepi2

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hi, Firefox 77.0.1 (32-bit) in Windows 7 crashed completely and i had to taskkill /im firefox.exe /f

this has happened a few times before, and up to this point Firefox could always restore the last session when reopened (maybe minus any last minute pages or any pages causing errors)

this time, the browser restored many pages, some of them are pages/tabs that i had already closed days before the crash (that i do not need) and also it didn't restore tens of tabs that i had opened afterwards (that i need) the missing tabs are not tabs that i opened right before the crash, they were open for at least one or two days in other words, the session restored is an earlier/older version and not the session i was having during/near the crash

is there something i can try to restore the correct session fully? would there be another restore file i can use? thank you for your time

hi, Firefox 77.0.1 (32-bit) in Windows 7 crashed completely and i had to taskkill /im firefox.exe /f this has happened a few times before, and up to this point Firefox could always restore the last session when reopened (maybe minus any last minute pages or any pages causing errors) this time, the browser restored many pages, some of them are pages/tabs that i had already closed days before the crash (that i do not need) and also it didn't restore tens of tabs that i had opened afterwards (that i need) the missing tabs are not tabs that i opened right before the crash, they were open for at least one or two days in other words, the session restored is an earlier/older version and not the session i was having during/near the crash is there something i can try to restore the correct session fully? would there be another restore file i can use? thank you for your time

All Replies (5)

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Sounds that Firefox hadn't updated sessionstore.jsonlz4 in the profile folder for a while and that the current sessionstore.jsonlz4 has an older session.

Backup the session files in the sessionstore-backups folder in the Firefox Profile Folder to make sure not to lose possible important session data.
Do NOT close Firefox when Firefox is already running.

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 (make sure to backup the current sessionstore.jsonlz4).

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

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

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cor-el said

[...]

hi, thank you for the reply, i wasn't able to follow your instructions (read on)

if i understood correctly you are telling me to take the session backup files and try them one by one by replacing the current session file (after backing up everything) am i with you so far?

- and, the backup files are inside the profiles \ [current profile] \ sessionstore-backups folder but where is the location of the main/current/active session file that i need to replace? i can see a sessionCheckpoints.json file but i can't find any sessionstore.jsonlz4 files inside the profiles \ [current profile] folder

- also, the files inside the session restore backup folder have a date modified of 06-20-2020 that is more than two weeks ago i suppose that this means there is nothing recent to be found correct?

- why did this happen though? my sessions are unreasonably large and those files are tens of megabytes are there any size limitations to those sessionstore files?

thank you

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the online tool has been unresponsive so far (10 minutes now, the files are too large it seems)

i will leave it open for a while to see if it ever finishes

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nope, i was trying to use the tool with Chrome i finally tried with Firefox and it crashed i have already backed up the whole profiles folder, hopefully it won't get any worse now

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unfortunately it seems that my Firefox has stopped making new sessionstore files completely so it's pretty much useless now

i'll go through the history listings to find the lost content, get the bookmarks, passwords etc and transfer them to a different browser, i can't see any other solution

even if i were to reinstall Firefox and sessionstore began working properly again, it would still be pointless because the problem might happen again, it's not reliable