مشكلة في الوصول الى static files في webpack

لدي مشروع هيكلته كالاتي 

assets
node_modules
src
package.json
package-lock.json
webpack.config.js

وهذا اعدادات webpack

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const CleanWebpackPlugin = require('clean-webpack-plugin');
const webpack = require('webpack');

module.exports = {
  entry: {
    app: './src/index.js'
  },
  devServer: {
    // contentBase: './dist',
    contentBase: __dirname + "/assets/",
    hot: true,
  },
  plugins: [
    new CleanWebpackPlugin(['dist']),
    new HtmlWebpackPlugin({
      title: 'Output Management'
    }),
    new webpack.NamedModulesPlugin(),
    new webpack.HotModuleReplacementPlugin()
  ],
  output: {
    path: __dirname + "/assets/",
    filename: 'bundle.js',
    chunkFilename: '[name].js'
  },
};

ولدي هذا الخطا داخل أدوات المطور

Content not from webpack is served from C:\Users\PC-user\WebstormProjects\untitled/assets/