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diff --git a/testing/web-platform/tests/scroll-animations/scroll-timelines/scroll-timeline-snapshotting.html b/testing/web-platform/tests/scroll-animations/scroll-timelines/scroll-timeline-snapshotting.html
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index 0000000000..1e43699d5b
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+++ b/testing/web-platform/tests/scroll-animations/scroll-timelines/scroll-timeline-snapshotting.html
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+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>ScrollTimeline snapshotting</title>
+<link rel="help" href="https://wicg.github.io/scroll-animations/#avoiding-cycles">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+<script src="/resources/testdriver-actions.js"></script>
+<script src="/web-animations/testcommon.js"></script>
+<script src="./testcommon.js"></script>
+
+<style>
+  body {
+    height: 800px;
+    width: 800px;
+  }
+</style>
+<div id="log"></div>
+
+<script>
+'use strict';
+
+promise_test(async t => {
+  const scroller = document.scrollingElement;
+  const maxScroll = scroller.scrollHeight - scroller.clientHeight;
+  const timeline = new ScrollTimeline({source: scroller});
+  scroller.scrollTo(0, 0);
+  assert_equals(scroller.scrollTop, 0, "verify test pre-condition");
+
+  scroller.scrollBy({top: 100, behavior: 'smooth'});
+  // Wait for the scroll to change.
+  const startScroll = scroller.scrollTop;
+  do {
+    await waitForNextFrame();
+  } while(scroller.scrollTop == startScroll);
+  assert_percents_equal(
+      timeline.currentTime,
+      (scroller.scrollTop / maxScroll) * 100,
+      'Scroll timeline current time corresponds to the scroll position.');
+}, 'ScrollTimeline current time is updated after programmatic animated ' +
+   'scroll.');
+
+</script>