1 files changed, 48 insertions, 0 deletions
diff --git a/testing/web-platform/tests/dom/events/scrolling/iframe-chains.html b/testing/web-platform/tests/dom/events/scrolling/iframe-chains.html
new file mode 100644
index 0000000000..fb7d674aae
--- /dev/null
+++ b/testing/web-platform/tests/dom/events/scrolling/iframe-chains.html
@@ -0,0 +1,48 @@
+<!DOCTYPE html>
+<html>
+<head>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-actions.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+<style>
+
+body { margin: 0; padding: 10px; }
+.space { height: 2000px; }
+
+#scroller {
+  border: 3px solid green;
+  position: absolute;
+  z-index: 0;
+  overflow: auto;
+  padding: 10px;
+  width: 250px;
+  height: 150px;
+}
+
+.ifr {
+  border: 3px solid blue;
+  width: 200px;
+  height: 100px;
+}
+
+</style>
+</head>
+<body>
+<div id=scroller>
+  <iframe srcdoc="SCROLL ME" class=ifr></iframe>
+  <div class=space></div>
+</div>
+<div class=space></div>
+<script>
+
+promise_test(async t => {
+  await new test_driver.Actions().scroll(50, 50, 0, 50).send();
+  // Allow the possibility the scroll is not fully synchronous
+  await t.step_wait(() => scroller.scrollTop === 50);
+}, "Wheel scroll in iframe chains to containing element.");
+
+</script>
+</body>
+</html>