Openid connect userinfo

The OpenID Connect API interface is a standard. Attempting to access userinfo of Corteza with:

http://localhost:18080/auth/oauth2/userinfo

via Postman by the “POST” method results in an error 405 “Method not allowed”. When using the GET method, the response is an HTML page that javascript is not enabled. To my knowledge, the “POST” method is the standard here.
Any idea?

I am also am unable to get a response out of the userinfo endpoint, and it appears to be necessary for connecting auth clients such as Keycloak or OpenUnison. Using GET and passing a valid access_token I always receive:

{“error”:“invalid_request”,“error_description”:“The request is missing a required parameter, includes an invalid parameter value, includes a parameter more than once, or is otherwise malformed”}

Are there any plans to implement the userinfo endpoint?