UBL-ExtensionContentDatatype-2.0.xsd

Is there a reason that ExtensionContentType changed from an
element without content in PRD2 to an empty element in PRD3?

PRD2:

      <xsd:any namespace="##any" minOccurs="0" maxOccurs="1" processContents="skip">
        
      </xsd:any>

PRD3:

      <xsd:any namespace="##any" minOccurs="0" maxOccurs="1" processContents="skip"/>

Jon