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Session doesn't restore after swapping sessionstore.jsonlz4 out

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I've followed the steps listed in many places on this forum and the web. (Thanks to jscher2000 for the excellent tech writing and support.) I've renamed all .jsonlz4 in the <Profile_folder>\sessionstore-backups folder. Sessionstore.jsonlz4 was moved from the <Profile_folder>, recovery-backup.jsonlz4 was copied into the <Profile_folder> and renamed Sessionstore.jsonlz4. Tabs don't restore , the Restore Session button is greyed out, and no tabs are listed in the Show tabs dropdown revealed window.

I know recovery-backup.jsonlz4 has the session I want to restore as I've examined it at https://www.jeffersonscher.com/ffu/scrounger.html. I can restore the tabs from the html file that page generates - but I had about 250 tabs open and that will be tedious. Is there any way to force Firefox to restore that session?

I'm running Firefox 66.0.1 64 bit on Windows 10 Professional x64 v1803 updated with all patches.

I've followed the steps listed in many places on this forum and the web. (Thanks to jscher2000 for the excellent tech writing and support.) I've renamed all .jsonlz4 in the <Profile_folder>\sessionstore-backups folder. Sessionstore.jsonlz4 was moved from the <Profile_folder>, recovery-backup.jsonlz4 was copied into the <Profile_folder> and renamed Sessionstore.jsonlz4. Tabs don't restore , the Restore Session button is greyed out, and no tabs are listed in the Show tabs dropdown revealed window. I know recovery-backup.jsonlz4 has the session I want to restore as I've examined it at https://www.jeffersonscher.com/ffu/scrounger.html. I can restore the tabs from the html file that page generates - but I had about 250 tabs open and that will be tedious. Is there any way to force Firefox to restore that session? I'm running Firefox 66.0.1 64 bit on Windows 10 Professional x64 v1803 updated with all patches.

Chosen solution

The file name needs to be all lowercase in case you capitalized it: sessionstore.jsonlz4

Did you verify that recovery-backup.jsonlz4 wasn't corrupted and is a valid file?

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All Replies (4)

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Chosen Solution

The file name needs to be all lowercase in case you capitalized it: sessionstore.jsonlz4

Did you verify that recovery-backup.jsonlz4 wasn't corrupted and is a valid file?

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File name was capitalized because of style - not while in the folder.

I've no idea if recovery-backup.jsonlz4 is corrupted and a valid file. But it's readable by https://www.jeffersonscher.com/ffu/scrounger.html.

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Did you check "History -> Recently Closed Tabs/Windows" if "Restore Previous Session" isn't available?

How big is this file (file size) and how many tabs are there?

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"History -> Recently Closed Tabs/Windows" shows the tast tabs and windows I had open as far as I can remember. File size of recovery-backup.jsonlz4 is 871 KB (892,326 bytes).

"...but I had about 250 tabs open..."