Add scripts

addScripts.js

const addScripts = urls => {
  let scriptsLoaded = 0;
  return new Promise((resolve, reject) => {
    urls.forEach((url) => {
      const script = document.createElement('script');
      script.src = url;
      document.head.appendChild(script); // or document.body
      script.onload = () => {
        scriptsLoaded++;
        if (scriptsLoaded === urls.length) {
          resolve();
        }
      };
    });
  });
}