I get an error when I try to login with Facebook

Since Apple updated to iOS 12 there is in some cases an error when using the Facebook login button. Here is how to avoid the error:

The error happens only when you click on [Login with Facebook] AND then click the button [Log in with the Facebook app].

Solution: You should not get this error, when you click on the other button. So [Log in with Facebook] and then click on [Log in with phone or email]