Similar to this Question I am trying to add a Role to a Group (Group Role Mapping). Except that in my case I need to add a client role instead of a realm role.
I tried to adapt the Answer in the mentioned question to my needs but sadly without success.
{SERVER}:81/auth/admin/realms/master/groups/{GROUP_ID}/role-mappings/
Gives me an "RESTEASY003650: No resource method found for POST, return 405 with Allow header"-error
I also tried adding the client in the path
{SERVER}:81/auth/admin/realms/master/groups/{GROUP_ID}/role-mappings/clients/{ID_OF_CLIENT[not Client-ID]}/
But doing this gives me an "unknown error"