aspnetcore: SignalR: System.ObjectDisposedException: Cannot access a disposed object. Object name: 'System.Net.Http.HttpClientHandler' when calling "await Connection.StartAsync();"

Describe the bug

When I try to connect to SignalR server in Xamarin App (UWP), where SignalR server is not available, I get the expected exception that server is not available:

System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Runtime.InteropServices.COMException: Der Text zu diesem Fehlercode wurde nicht gefunden.

Die Serververbindung konnte nicht hergestellt werden.

This is fine, but when I now start the AspNet Core SignalR server and try to connect again to SignalR service (without restarting the app) I get this unexpected exception:

System.ObjectDisposedException: Cannot access a disposed object.
Object name: 'System.Net.Http.HttpClientHandler'.

To Reproduce

Steps to reproduce the behavior:

1. Using this version of ASP.NET Core ‘…’ https://www.nuget.org/packages/Microsoft.AspNetCore.SignalR.Client/1.1.0
2. Run this code ‘…’

Expected behavior

Attempt to connect to SignalR should now find the started Server and connection should be started correctly.

Screenshots

Additional context

• VS2017 15.9.6
• Xamarin.Forms 3.4 Solution with UWP (MinVersion 16299, Target: 17763)