`], {type: 'text/html'})) }); window.onmessage = (evt) => { const [id, src] = evt.data; iframe.remove(); const check = Object.assign(document.createElement('iframe'), {src: src}) check.onload = () => console.log('loadable after iframe GC'); check.onerror = () => console.log('error after iframe GC'); document.body.append(check); } iframe.onload = () => { iframe.contentWindow.postMessage('post-GC', '*'); } document.body.append(iframe); Edit in JS Bin