// https://html.spec.whatwg.org/multipage/interaction.html#toggleevent
[Exposed=Window]
interface ToggleEvent : Event {
    constructor(DOMString type, optional ToggleEventInit eventInitDict = {});
    readonly attribute DOMString oldState;
    readonly attribute DOMString newState;
    readonly attribute Element? source;
};

dictionary ToggleEventInit : EventInit {
    DOMString oldState = "";
    DOMString newState = "";
    Element? source = null;
};
