<div class="item-one">
  <div class="item-two">
    <div class="item-three">
      <div class="item-four"></div>
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  </div>
</div>

window.addEventListener('load', function() {

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<div class="item-one">
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            <div class="item-three">
              <div class="item-four">
                <div class="item-one">
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                    <div class="item-three">
                      <div class="item-four">...and so on...</div>
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      </div>
    </div>
  </div>
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