css/css-display/display-change-iframe.html

<!DOCTYPE html>
<html class="reftest-wait">
  <link rel="author" title="Morten Stenshorne" href="mailto:mstensho@chromium.org">
  <link rel="help" href="https://www.w3.org/TR/css-display-3/#outer-role">
  <link rel="help" href="https://html.spec.whatwg.org/multipage/rendering.html#replaced-elements">
  <link rel="match" href="../reference/ref-filled-green-100px-square.xht">
  <p>Test passes if there is a filled green square and <strong>no red</strong>.</p>
  <iframe id="victim" src="support/red-square.html" style="width:100px; height:100px; border:none;"></iframe>
  <script>
    var loaded_once = false;
    victim.onload = function() {
        // The child document should only load once. It should not be reloaded
        // by changing the display type of the IFRAME.
        if (loaded_once)
            return;
        loaded_once = true;
        var childDoc = victim.contentWindow.document;
        // Change the red background to green. This will revert back to red if
        // the document gets reloaded (which shouldn't happen) when re-attaching
        // #victim.
        childDoc.getElementById("square").style.background = "green";
        document.offsetTop;
        victim.style.display = "block";
        document.documentElement.className = "";
    }
  </script>
</html>