AllowGetAuthenticateRequests doesn't appear to be working

I upgraded to 5.5 and definitely set AllowGetAuthenticateRequests to true. However, when logging in via Okta, I’m getting 403 forbidden now.

 Plugins.Add(new AuthFeature(() =>
                 new DVAuthUserSession(),
                 new ServiceStack.Auth.IAuthProvider[] {
                     new DVCredentialsAuthProvider(new AppSettings()) { SessionExpiry = TimeSpan.FromDays(7)  },
                     new DVBasicAuthProvider() {SessionExpiry = TimeSpan.FromMinutes(10) },
                     new DVOktaAuthProvider(new AppSettings()) { SessionExpiry = TimeSpan.FromDays(7)  }
                 HtmlRedirect = null,
                 AllowGetAuthenticateRequests = req => true

Can you post the raw HTTP Response Headers showing the full Error Response.

I have determined this is a different error than I thought, and will make another post with a better title