<!DOCTYPE html>
<script src="../resources/runner.js"></script>
<!-- This is a micro benchmark to catch an unintentional regression.
     If the reason of a regression is clear, it is okay.
     We do not have to optimize the result of the benchmark. -->
<div id="wrapper">
  <div id="host"></div>
</div>
<script>
'use strict';
const numChildOfHost = 50;
const numDivsInShadow = 20;
const loops = 20;

const slot1 = document.createElement('slot');
slot1.setAttribute('name', 'slot1');
const slot2 = document.creat