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diff --git a/testing/web-platform/tests/scroll-animations/css/animation-timeline-multiple.html b/testing/web-platform/tests/scroll-animations/css/animation-timeline-multiple.html
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+<!DOCTYPE html>
+<title>animation-timeline with multiple timelines</title>
+<link rel="help" src="https://drafts.csswg.org/css-animations-2/#animation-timeline">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/web-animations/testcommon.js"></script>
+<style>
+  main > div {
+    overflow: hidden;
+    width: 100px;
+    height: 100px;
+  }
+  main > div > div {
+    height: 200px;
+    width:  200px;
+  }
+
+  @keyframes top {
+    from { top: 100px; }
+    to { top: 200px; }
+  }
+  @keyframes bottom {
+    from { bottom: 100px; }
+    to { bottom: 200px; }
+  }
+  @keyframes left {
+    from { left: 100px; }
+    to { left: 200px; }
+  }
+  @keyframes right {
+    from { right: 100px; }
+    to { right: 200px; }
+  }
+
+  #top_scroller {
+    scroll-timeline: block top_timeline;
+  }
+  #bottom_scroller {
+    scroll-timeline: inline bottom_timeline;
+  }
+  #left_scroller {
+    scroll-timeline: block left_timeline;
+  }
+  #right_scroller {
+    scroll-timeline: inline right_timeline;
+  }
+
+  #element {
+    animation-name: top, bottom, left, right;
+    animation-duration: 10s;
+    animation-timing-function: linear;
+    animation-timeline: top_timeline, bottom_timeline, left_timeline, right_timeline;
+  }
+  /* Ensure stable expectations if feature is not supported */
+  @supports not (animation-timeline:foo) {
+    #element { animation-play-state: paused; }
+  }
+</style>
+<main>
+  <div id=top_scroller><div></div></div>
+  <div id=bottom_scroller><div></div></div>
+  <div id=left_scroller><div></div></div>
+  <div id=right_scroller><div></div></div>
+  <div id=element></div>
+</main>
+<script>
+  // Force layout of scrollers.
+  top_scroller.offsetTop;
+  bottom_scroller.offsetTop;
+  left_scroller.offsetTop;
+  right_scroller.offsetTop;
+
+  top_scroller.scrollTop = 20;
+  top_scroller.scrollLeft = 40;
+  bottom_scroller.scrollTop = 20;
+  bottom_scroller.scrollLeft = 40;
+  left_scroller.scrollTop = 60;
+  left_scroller.scrollLeft = 80;
+  right_scroller.scrollTop = 60;
+  right_scroller.scrollLeft = 80;
+
+  promise_test(async (t) => {
+    await waitForNextFrame();
+    assert_equals(getComputedStyle(element).top, '120px');
+    assert_equals(getComputedStyle(element).bottom, '140px');
+    assert_equals(getComputedStyle(element).left, '160px');
+    assert_equals(getComputedStyle(element).right, '180px');
+  }, 'animation-timeline works with multiple timelines');
+
+</script>