<!DOCTYPE html>
<html>
<head>
<script>
if (window.testRunner)
  testRunner.dumpAsText();
</script>
<style>
.one::before {
  float: left;
  content: "B";
}
.two::before {
  float: left;
  content: "A";
}
</style>
</head>
<body>
<input style="flex-direction: column;" class="one" type="range">
</body>
<script>
for (let i = 0; i < 100; ++i) {
  (i % 2) ? document.querySelector("input").classList = "one" : document.querySelector("input").classList = "two";
  document.body.offsetHeight;
}
</script>
<body>
<p>Test passes if it does not crash.</p>
</body>
</html>