<!DOCTYPE html>

  <meta charset="UTF-8">

  <title>CSS Reftest Reference</title>

  <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">

  <style>
  input
    {
      background-color: yellow;
      color: green;
      font-family: monospace;
      font-size: 48px;
      line-height: 56px;
      padding: 0px;
      width: 13ch;
    }
  </style>

  <script>
  function startReference()
  {
    /*
    Some browsers, like Chromium 80+ or Safari 14+, will
    transfer focus to a selected element like a text input
    and therefore style the border of such element according
    to an user agent stylesheet rule, such as:
    :focus {outline: -webkit-focus-ring-color auto 1px;} .
    So, we deliberately trigger such focus with the focus()
    method in the reference file.
    */

    document.getElementById("ref").focus();

    /*
    When a text input element is focused in Firefox
    82+, then the caret becomes visible and blinking and
    it is painted with the ::selected's color which is
    the green color in this case. We therefore counter,
    neutralize this by resetting the caret's color to the
    background color.
    */

    document.getElementById("ref").style.caretColor = "yellow";
  }
  </script>

  <body onload="startReference();">

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

  <div><input id="ref" type="text" value="Selected Text"></div>