Customize unauthorized content with the Router component in ASP.NET Blazor

The Router component, in conjunction with the AuthorizeRouteView component, allows the app to specify custom content if:

• The user fails an [Authorize] condition applied to the component. The markup of the <NotAuthorized> element is displayed. The [Authorize] attribute is covered in the [Authorize] attribute section.
• Asynchronous authorization is in progress, which usually means that the process of authenticating the user is in progress. The markup of the <Authorizing> element is displayed.
• Content isn’t found. The markup of the <NotFound> element is displayed.

<CascadingAuthenticationState>
    <Router AppAssembly="@typeof(Program).Assembly">
        <Found Context="routeData">
            <AuthorizeRouteView RouteData="@routeData" 
                DefaultLayout="@typeof(MainLayout)">
                <NotAuthorized>
                    <h1>Sorry</h1>
                    <p>You're not authorized to reach this page.</p>
                    <p>You may need to log in as a different user.</p>
                </NotAuthorized>
                <Authorizing>
                    <h1>Authorization in progress</h1>
                    <p>Only visible while authorization is in progress.</p>
                </Authorizing>
            </AuthorizeRouteView>
        </Found>
        <NotFound>
            <LayoutView Layout="@typeof(MainLayout)">
                <h1>Sorry</h1>
                <p>Sorry, there's nothing at this address.</p>
            </LayoutView>
        </NotFound>
    </Router>
</CascadingAuthenticationState>

References
https://docs.microsoft.com/en-us/aspnet/core/blazor/security/?view=aspnetcore-6.0#customize-unauthorized-content-with-the-router-component