图片loader: 'url?limit>40000'，图片不转base64时，若添加sourceMap不显示

[zengkun]

配置 publicPath 可显示；

output: {
    path: BUILD_PATH,
    **publicPath: 'http://localhost:8080/',**
    filename: '[name].js'
  },

https://github.com/webpack-contrib/style-loader/issues/55