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diff --git a/gfx/layers/apz/test/mochitest/helper_scroll_snap_no_valid_snap_position.html b/gfx/layers/apz/test/mochitest/helper_scroll_snap_no_valid_snap_position.html
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+++ b/gfx/layers/apz/test/mochitest/helper_scroll_snap_no_valid_snap_position.html
@@ -0,0 +1,45 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1">
+  <title>No snapping occurs if there is no valid snap position</title>
+  <script src="apz_test_utils.js"></script>
+  <script src="apz_test_native_event_utils.js"></script>
+  <script src="/tests/SimpleTest/paint_listener.js"></script>
+  <style>
+    div {
+      position: absolute;
+    }
+    #scroller {
+      width: 100%;
+      height: 500px;
+      overflow-y: scroll;
+      scroll-snap-type: y mandatory;
+    }
+    .child {
+      width: 100%;
+      height: 100px;
+      background-color: blue;
+    }
+  </style>
+</head>
+<body>
+  <div id="scroller">
+    <div class="child" style="top: 0px;"></div>
+    <div style="width: 100%; height: 2000px;"></div>
+    <div class="child" style="top: 1000px;"></div>
+  </div>
+  <script type="application/javascript">
+    async function test() {
+      await promiseMoveMouseAndScrollWheelOver(scroller, 100, 100);
+
+      ok(scroller.scrollTop > 0, "Scroll should happen some amount");
+    }
+
+    waitUntilApzStable()
+    .then(test)
+    .then(subtestDone, subtestFailed);
+  </script>
+</body>
+</html>