dy;

    promise_setup(async () => {
        const iframe = document.querySelector("iframe");
        await new Promise((resolve) => {
            iframe.onload = resolve;
            iframe.src = "about:blank";
        });
        iframeDoc = iframe.contentDocument;
        iframeBody = iframeDoc.body;
    });
    /**
     *
     * @param {Document} doc
     * @param {HTMLElement} value
     * @returns {Promise<Event>}
     */
    function makeChangeListener(doc) {
        return new Promise((resolve) => {