Here’s how you can permanently remove it from your system and a look at where it came from.
Open Control Panel and go to User Accounts.
Click Manage Web Credentials and you will be able to see the login information that has been saved for a myriad of accounts.
The good news is you might be able to tell which app stored it since Windows 10 identifies it when it can. In my case it was an unknown app.
Expand the login information from the dropdown arrow and click the ‘Remove’ button at the bottom to remove the information.
What’s troubling here is that if you click the ‘Show’ button you can actually look at your Facebook password. If you were to accidentally leave your system unlocked then you run the risk of exposing your password to someone who knows where to look for it.
If you ever let Edge save your Facebook credentials then simply removing them from Edge will ensure they are removed from Windows 10 but the same can’t be said for other apps which, as seen above, Windows 10 fails to identify at times.
It’s unlikely that Edge or even the Facebook app are the culprits so the only thing that can be done is to be selective with apps that we sign into Facebook with.