<link rel="match" href="reference/clip-path-polygon-ref.html" />
<style>
  .comment {
      position: absolute;

      left: 20px;
      width: 100px;
      height: 50px;

      border: 1px solid black;
  }

  .comment::before {
    position: absolute;
    right: 100%;
    width: 8px;
    height: 16px;
    pointer-events: none;
    content: " ";
    background-color: black;
    clip-path: polygon(0 50%, 100% 0, 100% 100%);
}
</style>
<div class=comment></div>