I'd like to create a dropdown list control in a form that allows users to either select a value from the list, or type a new value. Typing a new value and saving the form will result in that new value being added to the list for future use. I realize this may not be the standard UX for a dropdown control, so what is a good way to visually differentiate to users the difference between picking an existing value and typing a completely new value? We'd like them to easily understand when they are adding a new value to the list instead of using an existing one.
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