chromium/third_party/blink/web_tests/external/wpt/css/css-pseudo/active-selection-012.html

<!DOCTYPE html>

  <meta charset="UTF-8">

  <title>CSS Pseudo-Elements Test: active selection and background-color (basic)</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="help" href="https://www.w3.org/TR/css-pseudo-4/#highlight-styling">
  <link rel="match" href="reference/active-selection-012-ref.html">


  <link rel="stylesheet" href="support/highlights.css">
  <style>
  div
    {
      background-color: red;
      color: fuchsia;
      display: inline;
      font-size: 300%;
    }

  div::selection
    {
      background-color: green;
      color: aqua;
    }

  /*
  Chromium 77.0.3855.0 and above create a background-color #334C00 or
  rgb(51, 76, 0) and not a green (#008000 or rgb(0, 128, 0)) background
  color.
  */
  </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 the background color of each glyph of "Selected Text" is green and <strong>not red</strong> while each glyph of "Selected Text" is aqua and <strong>not fuchsia</strong>.

  <div id="test" class="highlight_reftest">Selected Text</div>