<img src="image.jpg" alt="Image">

<!-- HTML -->
<img src="thumbnail.jpg" alt="Thumbnail" id="thumbnail">

<script>
  // JavaScript
  var thumbnail = document.getElementById("thumbnail");
  thumbnail.addEventListener("click", function() {
    // 在这里执行弹出图像的操作
    var image = document.createElement("img");
    image.src = "image.jpg";
    document.body.appendChild(image);
  });
</script>