I have the same question as davs but I don't understand the directions in the link.
For instance, what is an "identifier?"
And, "if the field is required, a value will have to be entered/selected when a user registers or attempts to edit the appropriate section of their account."
Since I've set the location as required upon registration, what does it mean that "a value will have to be entered/selected?"
I'm sure I'd have other questions, but maybe if I can at least get passed the first two the rest will become clearer to me.