ECMAScript dynamic import without CSP violation errors

importViaScript.mjs

export default url => new Promise((res, rej) => {
  const script = document.createElement("script");
  script.src = url;
  script.type = "module";
  const onload = () => {
    script.remove();
    res(import(url));
  };
  const onerror = error => {
    script.remove();
    rej(error);
  };
  script.addEventListener("load", onload, { once: true });
  script.addEventListener("error", onerror, { once: true });
  document.head.append(script);
});