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diff --git a/gfx/layers/apz/test/mochitest/test_scroll_inactive_flattened_frame.html b/gfx/layers/apz/test/mochitest/test_scroll_inactive_flattened_frame.html
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+++ b/gfx/layers/apz/test/mochitest/test_scroll_inactive_flattened_frame.html
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+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test scrolling flattened inactive frames</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script src="/tests/SimpleTest/paint_listener.js"></script>
+  <script type="application/javascript" src="apz_test_utils.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<div id="container" style="height: 300px; width: 600px; overflow: auto; background: yellow">
+ <div id="outer" style="height: 400px; width: 500px; overflow: auto; background: black">
+  <div id="inner" style="mix-blend-mode: screen; height: 800px; overflow: auto; background: purple">
+  </div>
+ </div>
+</div>
+<script class="testbody" type="text/javascript">
+async function test() {
+  var container = document.getElementById("container");
+  var outer = document.getElementById("outer");
+  var inner = document.getElementById("inner");
+  var outerScrollTop = outer.scrollTop;
+  var containerScrollTop = container.scrollTop;
+  var event = {
+    deltaMode: WheelEvent.DOM_DELTA_LINE,
+    deltaX: 0,
+    deltaY: 10,
+    lineOrPageDeltaX: 0,
+    lineOrPageDeltaY: 10,
+  };
+  await new Promise(resolve => {
+    sendWheelAndPaint(inner, 20, 30, event, resolve);
+  });
+  ok(container.scrollTop == containerScrollTop, "container scrollframe should not have scrolled");
+  ok(outer.scrollTop > outerScrollTop, "nested scrollframe should have scrolled");
+}
+
+SimpleTest.waitForExplicitFinish();
+
+pushPrefs([["general.smoothScroll", false],
+           ["mousewheel.transaction.timeout", 1000000],
+           ["test.events.async.enabled", true]])
+.then(waitUntilApzStable)
+.then(test)
+.then(SimpleTest.finish, SimpleTest.finishWithFailure);
+
+</script>
+</body>
+</html>