chromium/third_party/blink/web_tests/css3/masking/mask-image-inline-block.html

<!DOCTYPE html>
<style>
.mask-image {
  background: blue;
  -webkit-mask-image: url("resources/circle.png");
  width: 400px;
  height: 300px;
}
</style>
<div style="display: inline-block" class="mask-image">&#xa0;</div>