chromium/third_party/blink/web_tests/external/wpt/css/css-pseudo/selection-contenteditable-011.html

<!DOCTYPE html>

  <meta charset="UTF-8">

  <title>CSS Pseudo-Elements Test: active selection and contenteditable element</title>

  <link rel="author" title="GĂ©rard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">
  <link rel="help" href="https://www.w3.org/TR/css-pseudo-4/#highlight-selectors">
  <link rel="match" href="reference/selection-contenteditable-011-ref.html">
  <!-- Allow different antialiased pixels on the focus ring. -->
  <meta name="fuzzy" content="0-5;0-255">

  <style>
  div
    {
      background-color: red;
      color: yellow;
      display: inline;
      font-size: 300%;
    }

  div::selection
    {
      background-color: yellow;
      color: green;
    }
  </style>

  <script>
  function startTest()
  {
  var targetRange = document.createRange();
  /* We first create an empty range */
  targetRange.selectNodeContents(document.getElementById("test"));
  /* Then we set the range boundaries to the children of div#test */
  window.getSelection().addRange(targetRange);
  /* Finally, we now select such range of content */
  }
  </script>

  <body onload="startTest();">

  <p>Test passes if each glyph of "Selected Text" is green with a yellow background and if there is <strong>no red</strong>.

  <div contenteditable="true" id="test">Selected Text</div>