The targetrole Attribute
The Current Definition of the targetrole Attribute
3.1.6. targetrole = CURIEs
The targetrole attribute specifies a space separated list of CURIEs that maps to an element with a role attribute with the same value.
If a targetid and a targetrole are both specified for an element, the targetid attribute value must take precedence.
If the prefix is omitted from a CURIE, the default value of http://www.w3.org/1999/xhtml/vocab# MUST be used.