Blazor Web App using the Razor pages (.razor) from RCL

Hello,

I'm trying to have the Razor Class Library (RCL) to serve the Razor pages (.razor) into Blazor Web App.

First, I created a RCL project called RazorClassLibrary and simply added a new Razor compnent (.razor page). The page is under a folder called Pages. the page is simple as below:
@page "/TestPage"

<h3>TestPage</h3>

@code {

}

then I created a new Blazor Web App that generated the template code the same solution

Added a reference to the RCL project that I created in the above step.

I added the new menu item in blazor web App by modifying the code in NavMenu.razor to href the /TestPage from RCL.
<div class="nav-item px-3">

 <NavLink class="nav-link" href="/TestPage">

     <span class="bi bi-list-nested-nav-menu" aria-hidden="true"></span> Test Page From RCL

 </NavLink>

</div>

I also modified the Routes.razor as below:
<Router AppAssembly="@typeof(Program).Assembly"

    AdditionalAssemblies="new[] { typeof(RazorClassLibrary.Pages.TestPage).Assembly }">

Nothing was done in App.razor

My Program.cs in Balzor web app has the code below that is unchanged from template generate code

using BlazorWebApp.Components;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

builder.Services.AddRazorComponents()

.AddInteractiveServerComponents();

var app = builder.Build();

// Configure the HTTP request pipeline.

if (!app.Environment.IsDevelopment())

{

app.UseExceptionHandler("/Error", createScopeForErrors: true);

// The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.

app.UseHsts();

}

app.UseHttpsRedirection();

app.UseStaticFiles();

app.UseAntiforgery();

app.MapRazorComponents<App>()

.AddInteractiveServerRenderMode();

app.Run();

After compiling and running it in IDE Localhost, I get 404 error
what am I missing?