#import 
// https://html.spec.whatwg.org/multipage/webappapis.html#promiserejectionevent
[Exposed=*]
interface PromiseRejectionEvent : Event {
    constructor(DOMString type, PromiseRejectionEventInit eventInitDict);
    readonly attribute object promise;
    readonly attribute any reason;
};
dictionary PromiseRejectionEventInit : EventInit {
    required object promise;
    any reason;
};