Why could Blazor CircuitHandler methods not get called?

I am trying to build a minimal working example of a CircuitHandler in a Blazor server side application but none of the CircuitHandler methods are called. I feel like I'm missing something obvious.

I'm developing on macOS Sonoma 14.5 using the .NET SDK Arm64 version 8.0.7.

I have used the dotnet commandline tool (version 8.0.303) to create a new project:

dotnet new blazor -o CircuitHandlerApp

In file MyCircuitHandler.cs I have added a simple CircuitHandler implementation:

using Microsoft.AspNetCore.Components.Server.Circuits;namespace CircuitHandlerApp;public class MyCircuitHandler : CircuitHandler{    public MyCircuitHandler()    {        Console.WriteLine("Constructor called.");    }    public override Task OnCircuitOpenedAsync(Circuit circuit, CancellationToken cancellationToken)    {        Console.WriteLine("OnCircuitOpenedAsync called.");        return base.OnCircuitOpenedAsync(circuit, cancellationToken);    }    public override Task OnConnectionUpAsync(Circuit circuit,         CancellationToken cancellationToken)    {        Console.WriteLine("OnConnectionUpAsync called.");        return Task.CompletedTask;    }    public override Task OnConnectionDownAsync(Circuit circuit,         CancellationToken cancellationToken)    {        Console.WriteLine("OnConnectionDownAsync called.");        return Task.CompletedTask;    }    public override Task OnCircuitClosedAsync(Circuit circuit, CancellationToken cancellationToken)    {        Console.WriteLine("OnCircuitClosedAsync called.");        return base.OnCircuitClosedAsync(circuit, cancellationToken);       }}

I have registered the handler in Program.cs like this:

...builder.Services.AddRazorComponents()    .AddInteractiveServerComponents();builder.Services.AddSingleton<CircuitHandler,MyCircuitHandler>();var app = builder.Build();...

In my interpretation of the documentation and other sources that should be enough to see some of the CircuitHandler methods being called. But that does not happen when I run the application and connect to it in the browser.

Also the constructor of MyCircuitHandler only gets called when I directly inject the CircuitHandler into one of the components.

On Github I didn't find any issues that sound similar to this problem and I would think that this feature is too essential that no one would have found a bug here before me. So it is probably more a configuration problem.

I have tried using the .NET 9 Preview but that didn't work either.

Here's the full Program.cs file:

using CircuitHandlerTest;using CircuitHandlerTest.Components;using Microsoft.AspNetCore.Components.Server.Circuits;var builder = WebApplication.CreateBuilder(args);// Add services to the container.builder.Services.AddRazorComponents()    .AddInteractiveServerComponents(options =>    {        options.DetailedErrors = true;    });builder.Services.AddSingleton<CircuitHandler, MyCircuitHandler>();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();