insertAfter

Inserts an HTML string after the end of the specified element.

Use el.insertAdjacentHTML() with a position of 'afterend' to parse htmlString and insert it after the end of el.

const insertAfter = (el, htmlString) =>
  el.insertAdjacentHTML("afterend", htmlString);

insertAfter(document.getElementById("myId"), "<p>after</p>");
// <div id="myId">...</div> <p>after</p>