- debug mode: response with config, url & benchmark millisec
- handle redirects in xhr and http: redirects: https://www.mattlunn.me.uk/blog/2012/05/handling-a-http-redirect-in-node-js/
- req._parseRequestBody: rewrite consider content-type header
- review _encodeQuery
- responseType: remove option, see restrtictions and pityfalls on MDN
- xhr onerror > error
- error catching json parse
- if (xhr.status < 299 && !result.error)
further
- ES6 modules