An automatically created JSON backup in the bookmarkbackups folder includes the item count in the file name. Does that show the expected number of bookmarks? *https://support.mozilla.org/en-US/kb/restore-bookmarks-from-backup-or-move-them Did you try to search for a known bookmark in case they ended up in an unexpected location ? In Firefox 96+ you can right-click a bookmark search/query/recent result list and click "Show in Folder" to locate this bookmark in the folder list. You can use the "Places Database" -> "Verify Integrity" button on the "Help -> More Troubleshooting Information" (about:support) page to get some stats about the bookmarks. If errors are reported with "Verify Integrity", close and restart Firefox or reboot and retry.