使用Net Core 3和HttpClient的HTTP / 2请求

Question

我正在尝试使用以下代码在C＃/ NetCore中发出HTTP / 2请求：

public static class WebClient
{
    public static void Main(string[] args) 
    {
        AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2Support", true);
        HttpResponseMessage response = Client.GetAsync("https://http2.pro/api/v1").Result;
        Console.WriteLine(response.Content.ReadAsStringAsync().Result);
        Console.WriteLine(response.Version);
    }

    private static readonly CookieContainer CookieContainer =
        new CookieContainer();

    private static readonly HttpClientHandler HttpClientHandler =
        new HttpClientHandler
        {
            CookieContainer = CookieContainer,
            MaxConnectionsPerServer = 5,
        };

    public static readonly HttpClient Client = new HttpClient(HttpClientHandler)
    {
        Timeout = Timeout.InfiniteTimeSpan,
        DefaultRequestVersion = new Version(2, 0)
    };
}

但是，服务器始终使用HTTP 1.1进行响应。有谁知道这是什么问题？如果重要的话，我正在Windows 7上使用Net Core 3.1.101。