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  <head>
    <script>
      onload = function() {
        var canvas2d = document.createElement('canvas')
        canvas2d.setAttribute('width', 0)
        document.body.appendChild(canvas2d)
        var ctx2d = canvas2d.getContext('2d')
        ctx2d.fillStyle = 'black'
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        ctx2d.fillRect(0, 0, 1, 1)
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  </head>
  <body>
  </body>
</html>
