Implemented interface member:
method
FirstWriteAsync
Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.IHttpOutputProducer.FirstWriteAsync(System.Int32, System.String, Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpResponseHeaders, System.Boolean, System.ReadOnlySpan<System.Byte>, System.Threading.CancellationToken)