Hi, this usually happens if Firefox signed you out of your Firefox account or created a new profile after an update or crash. First, check if you are signed in to the same Firefox account you used before, because bookmarks are restored through Sync. Also try typing about:profiles in the address bar to see if your old profile is still there and set it as default. If you recently refreshed or reinstalled Firefox, your old bookmarks may be in the “Old Firefox Data” folder on your computer and can be imported back.