eElement('slot');
slot2.setAttribute('name', 'slot2');
const shadowRoot = host.attachShadow({mode: 'open'});
shadowRoot.appendChild(slot1);
shadowRoot.appendChild(slot2);

for (let i = 0; i < numDivsInShadow; ++i) {
  let div = document.createElement('div');
  shadowRoot.appendChild(div);
}

function run() {
  for (let i = 0; i < loops; ++i) {
    for (let j = 0; j < numChildOfHost; ++j) {
      let div1 = document.createElement('div');
      div1.setAttribute('slot', 'slot1');
      host.appendChild(div1);