[keycloak-user] Is it possible to map 'sub' claim of external identity provider to attribute

I have configured an external OIDC identity provider and now want to add a mapper that maps the OIDC sub (subject) claim to a user attribute: Mapper type: Attribute Importer Claim: sub User Attribute Name: test On my client I have added a mapper that takes this attribute and inserts it into a claim: Mapper type: User Attribute User Attribute: test Token Claim Name: test Claim JSON Type: String On login, I expect to see the claim ‘test’ in the other claims collection, but the collection remains empty. Am I doing something wrong or is mapping of sub not supported? Rens