Impossible to add ressource openldap in a role

I detected a bug

Impossible to add ressource openldap in a role. However, the resource is correctly created, and the provisioning and synchronization works well between midpoint and the openldap resource.

The mapping between the attribute of the ressource "sn" and the attribute of the user "familyName" works well except when I tried to add the ressource in a role.

TThe error in the logs:

Caused by com.evolveum.midpoint.util.exception.SchemaException: Cannot find definition of a subitem familyName of ObjectDeltaObject(role:897a48fc-5fc5-4edd-8e92-ca59c72a399d(Employee) + null = role:897a48fc-5fc5-4edd-8e92-ca59c72a399d(Employee))

To reproduce the error, you can simply the tutorial:  MidPoint Tutorial, Chapter I: Deployment and Overview 

https://www.youtube.com/watch?v=LFWQl-FDR1w

The tutorial is no longer functional.

Do you have any idea where the problem comes from?

Thanks