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Extended Attributes were deprecated in Registry v3.3.0, and are removed entirely as of Registry v5.0.0. Transmogrification will convert Extended Attributes to Ad Hoc Attributes using the Extended Attribute name field as the Ad Hoc Attribute tag. The Extended Attribute display_name field is discarded.
External Identities (formerly Organizational Identities) Require Affiliations
In Registry v4.x and earlier, affiliation was not a required field for OrgIdentities. However, in Registry v5, affiliation for ExternalIdentityRole is required. Prior to Trnsmogrification, affiliations should be assigned to any OrgIdentities that don't have them, or the OrgIdentity will not transmogrify.
Organizational Identity Pooling No Longer Supported
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