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Bookmarks and Firefox previous sessions all saved as jsonlz4 sometime now. How do I reverse this to js?

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  • Last reply by cor-el

Kikko
Kikko
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I realised that my bookmarks and previous sessions are being saved as jsonlz4 as opposed to js that was the norm. Is that part of an update? Can it be changed back? When Firefox crashes I usually bring up the previous session by renaming it and copying it as sessionstore.js into the main firefox profile. Is that now possible? I think I read that jsonlz4 is the compressed version of the file. thanks.

I realised that my bookmarks and previous sessions are being saved as jsonlz4 as opposed to js that was the norm. Is that part of an update? Can it be changed back? When Firefox crashes I usually bring up the previous session by renaming it and copying it as sessionstore.js into the main firefox profile. Is that now possible? I think I read that jsonlz4 is the compressed version of the file. thanks.

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cor-el
cor-el
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The change to LZ4 compressed .jsonlz4 files is to speed up writing and reading these files and keep the disk access as low as possible. You can't reverse this, but Firefox can still read uncompressed files creates by older Firefox versions. For the bookmarks only automatically created backups in the bookmarkbackups folder are compressed and a manually created JSON backup is not compressed.

You now need to copy a compressed sessionstore file to sessionstore.jsonlz4 in the main profile folder to restore this session instead of using sessionstore.js.

Firefox can still restore uncompressed sessionstore files, but to make this work you need to remove (rename) compressed files and rename the sessionstore-backups folder to ensure that Firefox can't fallback to compressed .jsonlz4 files.