In virtual/interface member IResponseBehavior.HandleAsync(MockHttpRequestContext, HttpResponseMessage, ResponseHandlerDelegate, CancellationToken), rename parameter next so that it no longer conflicts with the reserved language keyword 'Next'. Using a reserved keyword as the name of a parameter on a virtual/interface member makes it harder for consumers in other languages to override/implement the member. (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1716)