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To use the reference token method set always_include_user_claims_in_id_token to 1 and the access_token_type_id to 2 or in Admin UI check the "Benutzerclaims in ID Token immer inkludieren" option in the client config and select “Access token type“ the Referenz , go into Admin UI; in the option “Access token type“, select the Reference option on the token tab.
In order to get the user claims, a call to the userinfo endpoint ({{idp_url}}/connect/userinfo) with a valid access token is needed.
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