Is it possible to call .Net 5 Grpc-Web from .Net Framework 4.7.2+ Windows Application?

Hi,

I am trying to convert my current .Net Framework Windows Application to consume Grpc-Web.
The code:
var httpHandler = new GrpcWebHandler(GrpcWebMode.GrpcWebText, new HttpClientHandler());
var channel = GrpcChannel.ForAddress(baseUri, new GrpcChannelOptions
{
HttpHandler = httpHandler
});
_client = new RService.RServiceClient(channel);

But it throws a exception:
Grpc.Core.RpcException
HResult=0x80131500
Message=Status(StatusCode="Internal", Detail="Error starting gRPC call. ArgumentException: Only supports HTTP/1.0 and HTTP/1.1 request

Is it possible to call .Net 5 Grpc-Web from .Net Framework 6.1+ Windows Application?

I appreciate for you help.

James Lin