var elem1removed = false; var elemParent = document.body; /* or whatever */ var observer = new MutationObserver(function(mutations) { mutations.forEach(function(mutation) { if (mutation.addedNodes && (mutation.addedNodes.length > 0)) { var node1 = mutation.target.querySelector('section.Paywall__footer-counter'); if (node1) { node1.parentNode.removeChild(node1); elem1removed = true; } if (elem1removed) { observer.disconnect(); } } }); }); observer.observe(elemParent, { childList: true, subtree: true });