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<!DOCTYPE HTML>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Test that scroll snap wont't happen on zoomed content</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>
    body {
      margin: 0;
    }
    html {
      overflow-y: scroll;
      scroll-snap-type: y proximity;
    }
    .snap {
      width: 100vw;
      height: 100vh;
      background-color: blue;
      position: absolute;
      top: 200px;
      scroll-snap-align: start;
    }
  </style>
</head>
<body>
  <div class="snap"></div>
  <div style="width: 100%; height: 500vh;"></div>
  <script type="application/javascript">
    async function test() {
      let transformEndPromise = promiseTransformEnd();
      // Use scrollToVisual() to scroll visual viewport.
      SpecialPowers.DOMWindowUtils.scrollToVisual(
        100, 400,
        SpecialPowers.DOMWindowUtils.UPDATE_TYPE_MAIN_THREAD,
        SpecialPowers.DOMWindowUtils.SCROLL_MODE_SMOOTH);
      // Wait for the end of the scroll.
      await transformEndPromise;
      await waitToClearOutAnyPotentialScrolls();
      const pageTop = visualViewport.pageTop;
      const pageLeft = visualViewport.pageLeft;
      let eventFired = false;
      window.visualViewport.addEventListener("scroll", () => {
        eventFired = true;
      });
      // Trigger a scroll snap, it should nothing.
      SpecialPowers.wrap(document.documentElement).mozScrollSnap();
      await waitToClearOutAnyPotentialScrolls();
      ok(!eventFired, "No visual scroll should happen");
      // Sanity checks to see whether the visual viewport hasn't been changed.
      is(visualViewport.pageTop, pageTop);
      is(visualViewport.pageLeft, pageLeft);
    }
    SpecialPowers.DOMWindowUtils.setResolutionAndScaleTo(10.0);
    waitUntilApzStable()
    .then(test)
    .then(subtestDone, subtestFailed);
  </script>
</body>
</html>