With that many copies, I assume that best is to restore and earlier backup in the bookmarkbackups folder that isn't affected. *https://support.mozilla.org/en-US/kb/restore-bookmarks-from-backup-or-move-them You may have to rename or remove places.sqlite in the Firefox profile folder in case of problems with restoring a backup. The name of automatically created JSON bookmarks backups in the bookmarkbackups folder includes a total item count (folders and separators included) and an hash value to prevent saving the same backup more than once. You also see this count in the Library Restore menu drop-down list. *bookmarks-YYYY-MM-DD_<item count>_<hash>.jsonlz4. ---- You can use the button in "Help -> More Troubleshooting Information" (about:support) to go to the current Firefox profile folder or use the <b>about:profiles</b> page (Root directory). *Help -> More Troubleshooting Information -> Profile Folder/Directory:<br>Windows: Open Folder; Linux: Open Directory; Mac: Show in Finder *https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data