Fix JS Content-Type in some Windows environments (#11)

server.go

@@ -215,6 +215,11 @@ func (s *Server) serve(rw http.ResponseWriter, req *http.Request, fn, suf, enc s
 	if ctype == "" {
 		ctype = "application/octet-stream" // Prevent unreliable Content-Type detection on compressed data.
 	}
+
+	// This is used to enforce application/javascript MIME on Windows (https://github.com/golang/go/issues/32350)
+	if strings.HasSuffix(req.URL.Path, ".js") {
+		ctype = "application/javascript"
+	}
 
 	rw.Header().Set("Content-Type", ctype)
 	rw.Header().Set("Etag", info.hash)