DASH 5th edition schema defines AdaptationSet@initializationPrincipal in clause 5.3.3.2 as
O - specifies the URL of an Initialization Segment that is sufficient to initialize the Adaptation Set. If not present, an Initialization Segment from one of the Representations is sufficent.
This new attribute is not present in the 5th edition schema
DASH 5th edition schema defines
AdaptationSet@initializationPrincipal
in clause 5.3.3.2 asThis new attribute is not present in the 5th edition schema