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Session Lost, Session Restore not working

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Windows restarted to update and all my 100s of tabs are lost (setting me back days of work!)... Firefox is set to always reopen previous tabs, but it didn't work. Recently closed tabs/windows are blank. The Restore Session page - about:sessionrestore - doesn't restore and lists no previous windows/tabs. I went into my sessionstore-backups folder and grabbed a previous.jsonlz4 that has some data but am not sure what to do with it.

Please help! This is a devastating loss of information, as I use my tabs as a to-do list and had many in-progress projects with resources that I cannot all recover just through history.

Windows restarted to update and all my 100s of tabs are lost (setting me back days of work!)... Firefox is set to always reopen previous tabs, but it didn't work. Recently closed tabs/windows are blank. The Restore Session page - about:sessionrestore - doesn't restore and lists no previous windows/tabs. I went into my sessionstore-backups folder and grabbed a previous.jsonlz4 that has some data but am not sure what to do with it. Please help! This is a devastating loss of information, as I use my tabs as a to-do list and had many in-progress projects with resources that I cannot all recover just through history.

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I tried to use that copied previous.jsonlz4 file but got this error in sessionstore-logs:

1718308459556 SessionStore ERROR The session file is invalid: : TypeError: state.windows[0] is undefined(resource:///modules/sessionstore/SessionStore.sys.mjs:1163:11) JS Stack trace: [email protected]:1163:11 onBeforeBrowserWindowShown/<@SessionStore.sys.mjs:2035:35

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Hi David, when you say you tried to use it, how did you try to use it? Could you take a look at this reply:

https://support.mozilla.org/en-US/questions/1449541?page=2#answer-1657106

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Aha! Yes, jscher2000, that did the trick! I was missing the last step: hiding the old sessionstore.jsonlz4.

I will also download Tab Session Manager just in case there's an issue again. I'd had this happen a year and a half ago on a different computer with a different Firefox account.

Thanks so much! Your instructions were so much clearer than I've been able to find before, and your speedy reply was a lifesaver. You have restored my faith in Firefox!

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Hi David, thank you for reporting back.

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Sual ver

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