1 files changed, 60 insertions, 0 deletions
diff --git a/testing/web-platform/tests/scroll-animations/scroll-timelines/animation-with-root-scroller.html b/testing/web-platform/tests/scroll-animations/scroll-timelines/animation-with-root-scroller.html
new file mode 100644
index 0000000000..6ba1a22445
--- /dev/null
+++ b/testing/web-platform/tests/scroll-animations/scroll-timelines/animation-with-root-scroller.html
@@ -0,0 +1,60 @@
+<html class="reftest-wait">
+<title>Scroll timeline with Web Animation using the root scroller</title>
+<link rel="help" href="https://drafts.csswg.org/scroll-animations/">
+<meta name="assert" content="Web animation correctly updates values when using the root scroller as the source for the ScrollTimeline">
+<link rel="match" href="animation-with-root-scroller-ref.html">
+
+<script src="/web-animations/testcommon.js"></script>
+<script src="/common/reftest-wait.js"></script>
+
+<style>
+  html {
+    min-height: 100%;
+    min-width: 100%;
+    padding-bottom: 100px;
+    padding-right: 100px;
+  }
+
+  #box {
+    width: 100px;
+    height: 100px;
+    background-color: green;
+  }
+
+  #covered {
+    width: 100px;
+    height: 100px;
+    background-color: red;
+  }
+</style>
+
+<div id="box"></div>
+<div id="covered"><p>Covered Contents</p></div>
+
+<script>
+  const box = document.getElementById('box');
+  const effect = new KeyframeEffect(box,
+    [
+      {transform: 'translateY(0)', opacity: 1},
+      {transform: 'translateY(200px)', opacity: 0}
+    ], {
+      duration: 1000,
+    }
+  );
+
+  const scroller = document.scrollingElement;
+  const timeline = new ScrollTimeline(
+      { source: scroller, orientation: 'block' });
+  const animation = new Animation(effect, timeline);
+  animation.play();
+
+  animation.ready.then(() => {
+    // Move the scroller to the halfway point.
+    const maxScroll = scroller.scrollHeight - scroller.clientHeight;
+    scroller.scrollTop = 0.5 * maxScroll;
+
+    waitForAnimationFrames(2).then(_ => {
+      takeScreenshot();
+    });
+  });
+</script>