Resize an iframe to fit its content

Assume that frame represents the iframe element.

frame.addEventListener('load', function () {
    // Get the height of the content
    const height = frame.contentDocument.body.scrollHeight;

    // Set the height of iframe
    frame.setAttribute('height', `${height}px`);
});

See also

• Attach or detach an event handler
• Show a loading indicator when an iframe is being loaded