text: exports.onCreateWebpackConfig = ({
    stage,
    actions,
    getConfig
  }) => {
    if (stage === 'build-html') {
      actions.setWebpackConfig({
        externals: getConfig().externals.concat(function(context, request, callback) {
          const regex = /^@?firebase(\/(.+))?/;
          // exclude firebase products from being bundled, so they will be loaded using require() at runtime.
          if (regex.test(request)) {
            return callback(null, 'commonjs ' + request); // <- use commonjs!
          }
          callback();
        })
      });
    }
  };
  
  