function waitForElm(selector) { return new Promise(resolve => { if (document.querySelector(selector)) { return resolve(document.querySelector(selector)); } const observer = new MutationObserver(mutations => { if (document.querySelector(selector)) { resolve(document.querySelector(selector)); observer.disconnect(); } }); observer.observe(document.body, { childList: true, subtree: true }); }); } waitForElm('.ief-entity-submit').then((elm) => { console.log('Element is ready'); console.log(elm.textContent); });