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pls help decompress jsonl4 bookmark file

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  • Last reply by cor-el

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After one of latest Firefox update (think it was around version 32) the bookmark file was compressed as "bookmarks_<date>....==.jsonlz4 file. After an update the new Firefox was not able to retrieve the compressed bookmark. I hope that here is a way to decompress this file outside the Firefox and retrieve it either as json or html file or a file that is retrievable by latest Firefox (34). The file is found in the following location:

C:\<user name>\AppData\Roaming\Mozilla\Firefox\Profiles\mvf52dyv.default

bookmark\bookmarks-2014-11-01-15....==.lzh bookmarkbackups\bookmarks-2014-11-01_15_....==.jsonlz4 The “mvf52dyv” is the from the old installation. The new one is tw145s6s.default To save it I renamed the “old” Mozilla directory to Mozilla_ before uninstalling and reinstalling a clean new version. Copied back the "old" jsonlz4 and "places.sqlite" to new "bookmarkbackups" directory but still no luck. One observation is that the new firefox (34 – just updated)) had jsonlz4 file and places.sqlite in a bookmarkbackups directory, while older versions has it at “<...>.default” directory level. Also, the new Firefox does not have bookmark directory, where the old one has in it bookmarks-<date>==.lzh file. I did try suggestion from the Firefox help pages to copy the old bookmarkbackups (with places.sqlite) into place of the new one, but that did not help. Even tried to copy the whole old mvf52dyv.default under new Mozilla directory, but this also did not work. Is this old bookmark lost for good or there is a hope to restore it? I will appreciate any help in restoring the content of the old bookmark. Regards

 Darko
After one of latest Firefox update (think it was around version 32) the bookmark file was compressed as "bookmarks_<date>....==.jsonlz4 file. After an update the new Firefox was not able to retrieve the compressed bookmark. I hope that here is a way to decompress this file outside the Firefox and retrieve it either as json or html file or a file that is retrievable by latest Firefox (34). The file is found in the following location: C:\<user name>\AppData\Roaming\Mozilla\Firefox\Profiles\mvf52dyv.default bookmark\bookmarks-2014-11-01-15....==.lzh bookmarkbackups\bookmarks-2014-11-01_15_....==.jsonlz4 The “mvf52dyv” is the from the old installation. The new one is tw145s6s.default To save it I renamed the “old” Mozilla directory to Mozilla_ before uninstalling and reinstalling a clean new version. Copied back the "old" jsonlz4 and "places.sqlite" to new "bookmarkbackups" directory but still no luck. One observation is that the new firefox (34 – just updated)) had jsonlz4 file and places.sqlite in a bookmarkbackups directory, while older versions has it at “<...>.default” directory level. Also, the new Firefox does not have bookmark directory, where the old one has in it bookmarks-<date>==.lzh file. I did try suggestion from the Firefox help pages to copy the old bookmarkbackups (with places.sqlite) into place of the new one, but that did not help. Even tried to copy the whole old mvf52dyv.default under new Mozilla directory, but this also did not work. Is this old bookmark lost for good or there is a hope to restore it? I will appreciate any help in restoring the content of the old bookmark. Regards Darko

Chosen solution

It is best to delete the places.sqlite file and only leave one compressed .jsonlz4 backup in the bookmarkbackups folder to make Firefox create a new places.sqlite file with the bookmarks from that file.

Also make sure to remove all places.sqlite files (-shm and -wal) if present.

You can check for problems with the places.sqlite database file in the Firefox profile folder.

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Chosen Solution

It is best to delete the places.sqlite file and only leave one compressed .jsonlz4 backup in the bookmarkbackups folder to make Firefox create a new places.sqlite file with the bookmarks from that file.

Also make sure to remove all places.sqlite files (-shm and -wal) if present.

You can check for problems with the places.sqlite database file in the Firefox profile folder.

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Thank you for the replay. With few attempts I was able to restore the “old” bookmark. Unfortunately, what I thought to be the old one has already been overwritten by an empty bookmark either during an update or one crash that happen around that time.

The interesting thing is that this “old” jsonlz4 file has date in name bookmarkbackups-2014-11-1-..., although the file time stamp is 9-26-2014, which I hoped contain the old bookmarks. The Sep date led me to believe that this is the old bookmark.

Can by any chance one of the two non-zero length files in minidump directory contain any sign of the lost bookmark?

For my benefits, where are the bookmarks stored now? With few sites added in the bookmark, only saw the places.sqlite being updated (in Roaming\...firefox\Profiles\<...>default\places.sqlite*). Did not find any file with name bookmark.*. At one exit saw boomarkbackups …. jsonlz4 file being updated (time stamp).

Regards

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Firefox only creates a new compressed .jsonlz4 backup if there has been changes to bookmarks. The hash ($$$$) that is appended to the file name in addition to the total count(xxxx) makes this possible.

  • bookmarks-####-##-##_xxxx_$$$$.json

This avoids creating unnecessary backups that would make older backup disappear.

Bug 818587 - Compress bookmark backups Bug 818399 - Smarter automatic bookmark backups Bug 818593 - Add file size to bookmarks restore UI Bug 818584 - Discard consecutive duplicate bookmark backups by comparing hashes