The type parameter is not implemented properly yet, there are a few
bugs. You aren't doing anything wrong.
You should stick to what is documented only, and if the behaviour
differs please let us know. We will always document what we support
and should be used.
any undocumented functionality will be either experimental or work in
progress.
The functionality might still have bugs, change without advance
warning and in some cases might even be dropped altogether. So we
would strongly recommend not to rely on it in production services.
We will update the documentation and let everyone know once it's fully
ready and officially supported.
Thanks
Filip
7digital