MVC Core 2.0 Demo: Logout causes 400 error

I am using the Okta okta-aspnetcore-mvc-example. The application runs fine and correctly authenticates against Okta. However logout always returns the 400 error:

The ‘post_logout_redirect_uri’ parameter must be an absolute URI that is whitelisted in the client app settings.
Likely I have missed a configuration setting, but I am unable to find it. I have done the following

What else do I need to configure this correctly?

Try setting your logout redirect to


instead of


Excellent, that worked.