Hi fmanesse, This usually happens when Firefox is reinstalled as a new profile. Try these steps: Open Firefox → Settings → General → Firefox Profile Folder → click Open Folder and check if there’s another profile with your old data. Go to Bookmarks → Manage Bookmarks → Import and Backup → Restore and see if an older backup is available. If you were signed in to a Firefox account before, sign in again and let bookmarks sync back. Hopefully this helps you recover your bookmarks.