We can use HTML within the ‘content’ field of our tooltip item. Replace the image src with the url of your image.

<script>
  window.wmTooltipItems = [
    {
      href: "#tooltip-with-image",
      content: `<img src="https://images.squarespace-cdn.com/content/v1/624b503d11269629b387b9c3/1649102910487-POB6XIE05ZPH03UR3ZG7/test-2.jpg?format=2500w">`,
    }
  ]
</script>
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Creating A Clickable Tooltip
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Tooltip with Image & Description