title: Identity Server 4, message.State is null or empty
body: <p>I keep receiving an error trying to authenticate using IdentityServer4.  I've looked at a few resources for this issue but all of them do not relate to my issue.
  I'm making a json request to <code>https://localhost:44377/signin-oidc</code> but this is what is logged from the AspCore Authentication DLL</p>
  
  <blockquote>
    <p>Microsoft.AspNetCore.Authentication.OpenIdConnect.OpenIdConnectMiddleware:Information: Error from RemoteAuthentication: OpenIdConnectAuthenticationHandler: message.State is null or empty..</p>
  </blockquote>
  
  <p>My Startup.cs configuration looks like this:</p>
  
  <pre><code>services.AddIdentityServer()
      .AddInMemoryIdentityResources(Config.GetIdentityResources())
      .AddInMemoryApiResources(Config.GetApiResources())
      .AddInMemoryClients(Config.GetClients())
      .AddTestUsers(Config.GetTestUsers())
      .AddTemporarySigningCredential();
  
  
  
  app.UseIdentityServer();
  app.UseCookieAuthentication(new CookieAuthenticationOptions { AuthenticationScheme = "cookie" });
  app.UseOpenIdConnectAuthentication(new OpenIdConnectOptions
  {
      ClientId = "openIdConnectClient",
      Authority = "https://localhost:44377/",
      SignInScheme = "cookie",
      TokenValidationParameters = new TokenValidationParameters
      {
          IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("clientpassword"))
      },
      CallbackPath = "/signin-oidc"
  });
  </code></pre>
  
  <p>And the Client I'm trying to Access looks like this</p>
  
  <pre><code>new Client
  {
      ClientId = "openIdConnectClient",
      ClientName = "Example Implicit Client Application",
      AllowedGrantTypes = GrantTypes.Implicit,
      AllowedScopes = new List&lt;string&gt;
      {
          IdentityServerConstants.StandardScopes.OpenId,
          IdentityServerConstants.StandardScopes.Profile,
          IdentityServerConstants.StandardScopes.Email,
          "role",
          "customAPI"
      },
      ClientSecrets = new List&lt;Secret&gt; {
          new Secret("superSecretPassword".Sha256())},
      RedirectUris = new List&lt;string&gt; {"https://localhost:44377/signin-oidc"},
      PostLogoutRedirectUris = new List&lt;string&gt; {"https://localhost:44377"}
  }
  </code></pre>