code: function copyPolyfills(pluginConfig, outputConfig) {
    if (
      !pluginConfig.polyfillDynamicImports &&
      !pluginConfig.polyfillWebcomponents &&
      !pluginConfig.polyfillBabel
    ) {
      return;
    }
    const polyfillsDir = `${outputConfig.dir.replace('/legacy', '')}/polyfills`;
    mkdirp.sync(polyfillsDir);
  
    if (pluginConfig.polyfillDynamicImports) {
      copyFileSync(
        path.resolve(pathJoin(__dirname, '../../src/dynamic-import-polyfill.js')),
        `${polyfillsDir}/dynamic-import-polyfill.js`,
      );
    }
  
    if (pluginConfig.polyfillWebcomponents) {
      copyFileSync(
        require.resolve('@webcomponents/webcomponentsjs/webcomponents-bundle.js'),
        `${polyfillsDir}/webcomponent-polyfills.js`,
      );
    }
  
    if (pluginConfig.polyfillBabel) {
      copyFileSync(
        require.resolve('@babel/polyfill/browser.js'),
        `${polyfillsDir}/babel-polyfills.js`,
      );
    }
  }
docs: Copy required polyfills from node_modules to the build directory