How do I highlight a property in CNContactViewCotnroller?

The documentation for hightlightProperty(withKey:identifier:) describes the parameter "key" as the "Key of the property to highlight." I believe that refers to the CNKeyDescriptor, such as CNContactGivenNameKey, which can cast from a type CNKeyDescriptor to String.

The documentation for identifier is "the value to highlight". I believe an example of that would be "John" as the given name.

Am I correct about all this?

In any case, I'm not able to highlight an email property when I use CNContactEmailAddresses as the key, and an actual email address as the identifier. I have also tried using the identifier property of CNLabeledValue<NSString>, which is how an email address is stored.

I can't find anything on the internet to explain this. I didn't even find a similar question, except my own question asking this exact same question about two months ago.

Anyone have any idea or a good answer for this?

How do I highlight a property in CNContactViewCotnroller?
 
 
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