Unable to select multiple values for an EFF attribute

Summary:

The client needs the ability to select multiple values for several EFF attribute. Tests were conducted using various display types —Drop Down, List of Values, Pop-Up List of Values, and Check Box Display Type—for EFF attributes. However, none of these options fulfill the requirement for selecting multiple values in one attribute field. This is crucial to our client — what would be the best approach to solve for it?

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