Troubleshooting development mode
Your project worked like a dream. then I try to modify it to run in HTTPS--first editing the product properties to be HTTPS in Visual Studio, using the recommended https: port number.

Eventually I found this dotnet/aspnetcore#1486, added the right extra references into the Startup.cs file, and now I can run https: at whatever port I want, but the hot swap recompilation stopped working.

I recreated the project from scratch. As soon as I uncomment the two commented lines below (Startup.cs), web site works fine, but hot module swap stops functioning.
.UseKestrel(options =>
{
var serverCertificate = LoadCertificate();
//options.UseHttps(serverCertificate);
})

            //.UseUrls("https://localhost:5001")