JSFiddle - React, Tailwind, and code Playground

HTML

TOP<br>
lorem ipsum<br>
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BOTTOM

JavaScript

$(document).ready(scrollDown());

function scrollUp() {
  console.log("up");
  $('body,html').animate({
    scrollTop: 0
  }, 3500, "linear", function() {
    scrollDown();
    return false;
  });
  return false;
}

function scrollDown() {
  console.log("down");
  $('body,html').animate({
    scrollTop: $(document).height()
  }, 5782, "linear", function() {
    scrollUp();
    return false;
  });

}