[horizon] Cross-domain user/role/project management

Hello, We run a cloud service with multiple keystone domains (Default domain and later we added a federated domain (AzureAD)). We are giving "federated domain users" roles on the projects in the Default domain which existed before the integration with AureAD. Is there a way to manage cross-domain role assignments in Horizon? A horizon setting I missed? I tried as admin and only users and projects of one domain at a time ever show up (I tried switching the domain context to Default and the federated domain). Thank you, Martin