if (R) {
                    d(R);
                    if ("undefined" != typeof e["fetch"]) {
                        var L = void 0;
                        try {
                            L = e["fetch"]()
                        } catch (e) {
                            L = e["fetch"]("about:blank") //error is here
                        }
                        L.then(function () {
                            return null
                        }, function () {
                            return null
                        });
                        if (L.constructor != R && L.constructor != F) d(L.constructor)
                    }
                }