Function addExtensionScript

test/unit/test-render-delaying-services.js:126–131

(win, extensionName)

}

function addExtensionScript(win, extensionName) {
  const scriptElement = win.document.createElement('script');
  scriptElement.setAttribute('async', '');
  scriptElement.setAttribute('custom-element', extensionName);
  win.document.head.appendChild(scriptElement);
}