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diff --git a/gfx/layers/apz/test/mochitest/helper_zoom_prevented.html b/gfx/layers/apz/test/mochitest/helper_zoom_prevented.html
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+++ b/gfx/layers/apz/test/mochitest/helper_zoom_prevented.html
@@ -0,0 +1,75 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <meta name="viewport" content="width=device-width">
+  <title>Checking prevent-default for zooming</title>
+  <script type="application/javascript" src="apz_test_native_event_utils.js"></script>
+  <script type="application/javascript" src="apz_test_utils.js"></script>
+  <script src="/tests/SimpleTest/paint_listener.js"></script>
+  <script type="application/javascript">
+
+async function testPreventDefault(aTouchStartToCancel) {
+  var initial_resolution = await getResolution();
+  ok(initial_resolution > 0,
+      "The initial_resolution is " + initial_resolution + ", which is some sane value");
+
+  // preventDefault exactly one touchstart based on the value of aTouchStartToCancel
+  var touchStartCount = 0;
+  var canceller = function(e) {
+    dump("touchstart listener hit, count: " + touchStartCount + "\n");
+    touchStartCount++;
+    if (touchStartCount == aTouchStartToCancel) {
+      dump("calling preventDefault on touchstart\n");
+      e.preventDefault();
+      document.documentElement.removeEventListener("touchstart", canceller, {passive: false});
+    }
+  };
+  document.documentElement.addEventListener("touchstart", canceller, {passive: false});
+
+  let touchEndPromise = new Promise(resolve => {
+    document.documentElement.addEventListener("touchend", resolve, {passive: true, once: true});
+  });
+
+  // Ensure that APZ gets updated hit-test info
+  await promiseAllPaintsDone();
+
+  await pinchZoomInTouchSequence(150, 300);
+  await touchEndPromise; // wait for the touchend listener to fire
+
+  // Flush state and get the resolution we're at now
+  await promiseApzFlushedRepaints();
+  let final_resolution = await getResolution();
+  is(final_resolution, initial_resolution, "The final resolution (" + final_resolution + ") matches the initial resolution");
+}
+
+function transformFailer() {
+  ok(false, "The test fired an unexpected APZ:TransformEnd");
+}
+
+async function test() {
+  // Register a listener that fails the test if the APZ:TransformEnd event fires,
+  // because this test shouldn't actually be triggering any transforms
+  SpecialPowers.Services.obs.addObserver(transformFailer, "APZ:TransformEnd");
+
+  await testPreventDefault(1);
+  await testPreventDefault(2);
+}
+
+function cleanup() {
+  SpecialPowers.Services.obs.removeObserver(transformFailer, "APZ:TransformEnd");
+}
+
+waitUntilApzStable()
+.then(test)
+.finally(cleanup)
+.then(subtestDone, subtestFailed);
+
+  </script>
+</head>
+<body>
+  Here is some text to stare at as the test runs. It serves no functional
+  purpose, but gives you an idea of the zoom level. It's harder to tell what
+  the zoom level is when the page is just solid white.
+</body>
+</html>