bulmil/dist/esm/polyfills/index.js

export function applyPolyfills() {
  var promises = [];
  if (typeof window !== 'undefined') {
    var win = window;

    if (!win.customElements ||
      (win.Element && (!win.Element.prototype.closest || !win.Element.prototype.matches || !win.Element.prototype.remove || !win.Element.prototype.getRootNode))) {
      promises.push(import(/* webpackChunkName: "polyfills-dom" */ './dom.js'));
    }

    function checkIfURLIsSupported() {
      try {
        var u = new URL('b', 'http://a');
        u.pathname = 'c%20d';
        return (u.href === 'http://a/c%20d') && u.searchParams;
      } catch (e) {
        return false;
      }
    }

    if (
      'function' !== typeof Object.assign || !Object.entries ||
      !Array.prototype.find || !Array.prototype.includes ||
      !String.prototype.startsWith || !String.prototype.endsWith ||
      (win.NodeList && !win.NodeList.prototype.forEach) ||
      !win.fetch ||
      !checkIfURLIsSupported() ||
      typeof WeakMap == 'undefined'
    ) {
      promises.push(import(/* webpackChunkName: "polyfills-core-js" */ './core-js.js'));
    }
  }
  return Promise.all(promises);
}