**Expected Behaviour** A request with the HTTP header: ``` Accept: application/json; charset=utf-8 ``` is accepted as a GraphQL request **Actual Behaviour** The request is rejected with: ``` HTTP 406 Not Acceptable ``` **Debug Information** I think the check here is wrong and should be looking for `utf-8` not `utf8`. https://github.com/graphql/graphql-http/blob/v1.22.0/src/handler.ts#L593