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How to make IE 8 not to show anythiny to an iFrame before onload element is finished?
function frameLoaded() {
sleep(3000); //simulating the time the script needs
var leftDiv = window.frames.testFrame.document.getElementById("leftcol");
leftDiv.style.display = "none";
}

function sleep(milliSeconds){
var startTime = new Date().getTime(); // get the current time
while (new Date().getTime() < startTime + milliSeconds); // hog cpu
}

function frameLoaded() {
  sleep(3000); //simulating the time the script needs
  var leftDiv = window.frames.testFrame.document.getElementById("leftcol");
  leftDiv.style.display = "none";
  document.getElementById("iframe").style.display = 'block';
}