Closest get past shadow dom

closestPastShadowDom.ts

const isShadowRoot = (maybeRoot) => {
    return maybeRoot && maybeRoot.toString() === '[object ShadowRoot]'
} 

const closestPastShadowDom = (elem, selector) => {
    const closest = elem.closest(selector);
    if(closest)
        return closest;

    const root = elem.getRootNode();

    if(isShadowRoot(root)) {
        return closestPastShadowDom((root).host, selector)
    }

    return undefined;
}