<html>
<head>
<style>
.test {
  width: 200px;
  height: 200px;
  border: 10px solid black;
  background-color: lime;
  -webkit-mask-image: url(url-not-found), url(url-not-found), url(url-not-found), url(url-not-found), url(url-not-found), url(url-not-found), url(url-not-found), url(url-not-found), url(url-not-found);
  -webkit-mask-position: top left, top right, bottom left, bottom right, top center, center right, bottom center, center left, center;
  -webkit-mask-origin: border;
  -webkit-mask-repeat: no-repeat, no-repeat, no-repeat, no-repeat, repeat-x, repeat-y, repeat-x, repeat-y, repeat;
  -webkit-mask-composite: copy;
}
</style>
</head>
<body>
  <div class="test">This text should be visible.</div>
  <p>If the test passes, you should see nothing above, because we should not render masked content if the mask image fails to load.</p>
</body>
</html>