message: build(env): fix fake env
diff: @@ -293,8 +293,9 @@ module.exports = {
  // Tailor locales
  new webpack.ContextReplacementPlugin(/moment[\\/]locale$/, /^\.\/(en|zh-cn|zh-tw)$/),
  new WrapperPlugin({
  - test: /webextension-page\.js$/,
  - footer: ';(function () {\n' + fackBgEnv + '\n})();'
  + test: /background\.js$/,
  + header: ';(function () {\n' + fackBgEnv + '\n',
  + footer: '\n})();'
  })
  ],
  // Some libraries import Node modules but don't use them in the browser.
  