export function renderExternal() {  const giteaExternalRender = document.querySelector('iframe.external-render');  if (!giteaExternalRender) return;   giteaExternalRender.contentWindow.postMessage({requestOffsetHeight: true}, '*');   const eventListener = (event) => {    if (event.source !== giteaExternalRender.contentWindow) return;    const height = Number(event.data?.frameHeight);    if (!height) return;    giteaExternalRender.height = height;    giteaExternalRender.style.overflow = 'hidden';    window.removeEventListener('message', eventListener);  };  window.addEventListener('message', eventListener);}