Disabling static directory listing (#4919)

web/web.go

@@ -37,6 +37,10 @@ func InitWeb() {
 func staticHandler(handler http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.Header().Set("Cache-Control", "max-age=31556926, public")
+		if strings.HasSuffix(r.URL.Path, "/") {
+			http.NotFound(w, r)
+			return
+		}
 		handler.ServeHTTP(w, r)
 	})
 }