<style>
.wrapper {
  position: relative;
  font-family: Ahem;
}

.shadow {
  position: relative;
  z-index: 1;
  font-size: 20px;
  text-shadow: 0px 100px 1px black;
}

.absolute {
  position: absolute;
  left: 0;
  top: 0;
  will-change: transform;
}
</style>

<div class="wrapper">
  <div class="shadow">PASS if this line is doubled.</div>
  <div class="absolute"></div>
</div>