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Open old window with >4000 tabs

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I know that you normally can only reopen the last two closed windows. But is there any other solution or trick to reopen more than the last two? It would mean alot, as this window had more than 4000 important tabs in it.

I know that you normally can only reopen the last two closed windows. But is there any other solution or trick to reopen more than the last two? It would mean alot, as this window had more than 4000 important tabs in it.

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I don't know if this will help: You may have corrupt sessionstore [v56] sessionstore.jsonlz4 file(s). Delete all sessionstore* files and the sessionstore-backups folder.

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. You can try to read out their contents using this tool: https://www.jeffersonscher.com/res/scrounger.html


Type about:support<enter> in the address box.

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.

Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder

Linux: Under the page logo on the left side, you will see Application Basics. Under this find Profile Directory. To its right press the button Open Directory.

Locate the above file. Then rename or delete it. Restart Firefox.

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You can try to restore a recent upgrade.jsonlz4-<build_id> when available or use a utility to browse Windows System Restore points to see if you can find a recent sessionstore.jsonlz4 file.

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

You can copy a file from the sessionstore-backups folder to the main profile with Firefox closed and rename the file to sessionstore.jsonlz4 to replace the current file.