chromium/third_party/blink/web_tests/external/wpt/html/editing/dnd/platform/interrupt/004.html

<!doctype html>
<title>File drag during prompt for upload</title>
<style>
  body > div {
    height: 200px;
    width: 200px;
    background-color: orange;
    display: inline-block;
  }
</style>
<script type="text/javascript">
window.onload = function () {
  var orange = document.getElementsByTagName('div')[0];
  orange.ondragenter = orange.ondragover = function (e) {
    e.preventDefault();
  };
  orange.ondrop = function (e) {
    e.preventDefault();
    document.getElementsByTagName('ol')[0].innerHTML = ( e.dataTransfer.files[0] && e.dataTransfer.files[0].name == 'pass.txt' ) ? 'PASS' : 'FAIL';
  };
};
</script>
<div draggable="true"></div>

<ol>
  <li>Save <a href="pass.txt">pass.txt</a> and <a href="fail.txt">fail.txt</a> onto your computer.</li>
  <li>Drag pass.txt from your computer onto the orange square.</li>
  <li>A prompt should appear. Do not dismiss it. If a prompt does not appear, ignore any further steps, and check the tests in ../../file/</li>
  <li>Drag fail.txt from your computer onto a blank part of this page. Fail if this page is replaced.</li>
  <li>Accept the prompt. Fail if nothing happens.</li>
</ol>