mozilla-release/testing/web-platform/tests/feature-policy/experimental-features/layout-animations-enabled-tentative.html

<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/css/support/interpolation-testcommon.js"></script>
<title> 'layout-animations' Policy : Correct behavior for affected and unaffected properties when
         feature is enabled.
</title>
<body>
<script>
  // The expectation for all the following properties could be the same (they are all of type length).
  let length_expectations_100_to_200 = [
      {at: 0.00, expect: "100px"},
      {at: 0.1,  expect: "110px"},
      {at: 0.2,  expect: "120px"},
      {at: 0.4,  expect: "140px"},
      {at: 0.6,  expect: "160px"},
      {at: 0.8,  expect: "180px"},
      {at: 0.9,  expect: "190px"},
  ];
  // Ensure all the affected animations run normally.
  ["bottom", "height", "left", "right", "top", "width"].forEach(
    (p) => test_interpolation({
                                property: p,
                                from: "100px",
                                to: "200px",
                                test_prefix: `Testing property "${p}".`
                              },
                              length_expectations_100_to_200));
</script>
</body>