The Windows 10 restore can preserve your data either where it used to be -- sounds like that didn't happen -- or in a temporary folder named C:\Windows.old '''Can you find such a folder on your system in you check Windows' File Explorer?''' ''If so:'' Before proceeding, please set Windows to show you hidden files and folders: https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files Then check here: C:\Windows.old\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\ You might just have one profile folder, or you might have more than one. The bookmark backup files are in a folder named '''bookmarkbackups''' in each profile. You can copy promising files to the Desktop to try in a Restore. Anything so far?