interface mixin InterestInvokerElement {
  [CEReactions,Reflect=interestfor] attribute Element? interestForElement;
};

HTMLAnchorElement includes InterestInvokerElement;
HTMLAreaElement includes InterestInvokerElement;
HTMLButtonElement includes InterestInvokerElement;
SVGAElement includes InterestInvokerElement;

[Exposed=Window]
interface InterestEvent : Event {
    constructor(DOMString type, optional InterestEventInit eventInitDict = {});
    readonly attribute Element? source;
};

dictionary InterestEventInit : EventInit {
    Element? source = null;
};