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debugging chrome extension
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  function init() {
      getdata();
  }

  var txt;
  function getdata() {
      var xhr = new XMLHttpRequest();
      xhr.open('GET',myurl, true);
      xhr.setRequestHeader('Cache-Control', 'no-cache');
      xhr.setRequestHeader('Pragma', 'no-cache');
      xhr.onreadystatechange = function() {
          if (xhr.readyState == 4) if (xhr.responseText) {
              txt = xhr.responseText;
          }
      }

      xhr.send();
      console.log(txt);
  }

...

<body onload="init();">

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