Question

<div id="containerDiv"></div>

#containerDiv {
  position: absolute;
  top: 0px;
  width: 400px;
  height: 100%;
  padding: 5px;
  font-size: .875em;
  overflow-y: scroll;
}

document.getElementById("containerDiv").innerHTML = variableLongText;

How to reset the scroll position back to top of container div the next time?

Answer 1

var myDiv = document.getElementById('containerDiv');
myDiv.innerHTML = variableLongText;
myDiv.scrollTop = 0;

See the scrollTop attribute.