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Firefox backup jsonlz4-file hasn't saved tabs for weeks? Now unable to restore

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  • Last reply by cor-el

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Today as I woke up my computer from sleep mode, Firefox was unresponsive and I had to use task manager to shut it down.

The problem after restarting Firefox is that I have or had probably over four thousand tabs open in my previous session (yes I know it's a ridiculous amount), but Firefox didn't restore several hundred of the most recent tabs.

I've had similar problems before but always managed to get all my tabs back from the sessionstore-backups -folder and JSONLZ4 -files located there. Currently the most recent upgrade.jsonlz4 -file shows the "Date modified" is 20.3. which is probably around the time I had problems the last time, which I resolved by moving such file to the main folder and renamed it sessionstore.js as per instructions, if I recall correctly.

Using "Session History Scrounger for Firefox" makes it seem evident that the latest/biggest jsonlz4 -file is still in the same condition (around 3500 tabs), i.e. hasn't saved any pages after the recovery I made last month. For now I haven't tried to recover anything using the same method as above in case there's still a chance to restore the full session I had open until last night.

So in essence my question is if the tabs opened between 20.3. and 8.4. are simply gone now? If that is the case I can live with it. But why hasn't or hadn't the jsonlz4 -file in sessionstore-backups saved any more pages after my last recovery from 20.3.? Or is there a file in some folder that I'm not aware of?

Today as I woke up my computer from sleep mode, Firefox was unresponsive and I had to use task manager to shut it down. The problem after restarting Firefox is that I have or had probably over four thousand tabs open in my previous session (yes I know it's a ridiculous amount), but Firefox didn't restore several hundred of the most recent tabs. I've had similar problems before but always managed to get all my tabs back from the sessionstore-backups -folder and JSONLZ4 -files located there. Currently the most recent upgrade.jsonlz4 -file shows the "Date modified" is 20.3. which is probably around the time I had problems the last time, which I resolved by moving such file to the main folder and renamed it sessionstore.js as per instructions, if I recall correctly. Using "Session History Scrounger for Firefox" makes it seem evident that the latest/biggest jsonlz4 -file is still in the same condition (around 3500 tabs), i.e. hasn't saved any pages after the recovery I made last month. For now I haven't tried to recover anything using the same method as above in case there's still a chance to restore the full session I had open until last night. So in essence my question is if the tabs opened between 20.3. and 8.4. are simply gone now? If that is the case I can live with it. But why hasn't or hadn't the jsonlz4 -file in sessionstore-backups saved any more pages after my last recovery from 20.3.? Or is there a file in some folder that I'm not aware of?

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You can try to rename the sessionstore-backups folder to see whether the new folder that Firefox should create will work better.

Does Firefox at least create a new sessionstore.jsonlz4 or does that file stay the same as well?

What is the file size of that sessionstore file as it may take too long to process this file and the process gets aborted?

There might also be a lot of information in the file about tab session history and closed tabs that could cause problems.