title: Found markup element with unexpected name 'Cascading AuthenticationState'
body: <p>I am getting this error on my App.razor:</p>
  <blockquote>
  <p>Found markup element with unexpected name
  'CascadingAuthenticationState'. If this is intended to be a component,
  add a @using directive for it namespace</p>
  </blockquote>
  <p>This is the code I am using</p>
  <pre><code>&lt;CascadingAuthenticationState&gt;
      &lt;Router AppAssembly=&quot;@typeof(Program).Assembly&quot;&gt;
          &lt;Found Context=&quot;routeData&quot;&gt;
              &lt;RouteView RouteData=&quot;@routeData&quot; DefaultLayout=&quot;@typeof(MainLayout)&quot; /&gt;
          &lt;/Found&gt;
          &lt;NotFound&gt;
              &lt;LayoutView Layout=&quot;@typeof(MainLayout)&quot;&gt;
                  &lt;p&gt;Sorry, there's nothing at this address.&lt;/p&gt;
              &lt;/LayoutView&gt;
          &lt;/NotFound&gt;
      &lt;/Router&gt;
  &lt;/CascadingAuthenticationState&gt;
  </code></pre>
  <p><a href="https://i.stack.imgur.com/Dstl0.png" rel="noreferrer"><img src="https://i.stack.imgur.com/Dstl0.png" alt="enter image description here" /></a></p>
  <p>I am using Visual Studio 2019 preview and I can run the application but, why do I have the red line in the Cascading....?</p>