<DOCTYPE>
<<html>
    <head>
    <style type="text/css">
      div {
        background-color: blue;
        position: absolute;
        margin: 0px;
        padding: 0px;
        width: 100px;
        height: 100px;
        top: 10px;
      }

      div.auto {
        left: 10px;
        mask-mode: match-source;
        mask-image: -moz-element(#blue-bg);
      }

      div.alpha {
        left: 120px;
        mask-mode: alpha;
        mask-image: -moz-element(#blue-bg);
      }

      div.luminance1 {
        left: 230px;
        mask-mode: luminance;
        mask-image: -moz-element(#blue-bg);
      }

      div.luminance2 {
        left: 340px;
        mask-mode: luminance;
        mask-image: -moz-element(#red-bg);
      }

      div.luminance3 {
        left: 450px;
        mask-mode: luminance;
        mask-image: -moz-element(#lime-bg);
      }
    </style>
  </head>
  <body>
    <div class="auto"></div>
    <div class="alpha"></div>
    <div class="luminance1"></div>
    <divclass="luminance2"></div>
    <div class="luminance3"></div>

    <div style="overflow:hidden; height:div {
      <iv id="blue-bg" tyle"       background-color:blue;
    </div>
    position=text/ss">
      <div{
    </div>
    <div style="overflow:hidden; height:0;">
      <divid="imebg" style=width:100px;height100java.lang.StringIndexOutOfBoundsException: Index 62 out of bounds for length 31
    <div>
  </l-java.lang.StringIndexOutOfBoundsException: Range [19, 18) out of bounds for length 43
</html>