How to use the @jupyterlab/buildutils.WPPlugin.FrontEndPlugin function in @jupyterlab/buildutils

return ['domelementtype', 'hash-base', 'inherits'].includes(
        instance.name
      );
    }
  }),
  new HtmlWebpackPlugin({
    chunksSortMode: 'none',
    template: plib.join('templates', 'template.html'),
    title: jlab.name || 'JupyterLab'
  }),
  new webpack.HashedModuleIdsPlugin(),

  // custom plugin for ignoring files during a `--watch` build
  new WPPlugin.FilterWatchIgnorePlugin(ignored),
  // custom plugin that copies the assets to the static directory
  new WPPlugin.FrontEndPlugin(buildDir, jlab.staticDir)
];

if (process.argv.includes('--analyze')) {
  plugins.push(new BundleAnalyzerPlugin());
}

module.exports = [
  {
    mode: 'development',
    entry: {
      main: ['whatwg-fetch', plib.resolve(buildDir, 'index.out.js')]
    },
    // Map Phosphor files to lumino files.
    resolve: {
      alias: {
        '@phosphor/algorithm$': plib.resolve(