Anyone have any idea about this? Experiencing the same issue, also using Authentik for my project, which claims to have native Rancher support. When I add users or groups to a project, cluster or namespace, the search doesn't work properly (you can enter anything and it will return a selectable result labelled "ADFS User") and adding a user / group will add them to the list, but they don't actually gain any real permissions and it just seems to be a visual thing.
Thanks in advance.