javascript - How does webpack remove duplicate css?

Question

a.css 内容:
*{
    margin:0;
}
b.css  内容:
*{
    padding:0;
    margin:0
}

The code after webpack packaging is

*{margin:0;}*{padding:0;margin:0}

The effect I want is

*{
   margin:0;padding:0
}

The following is the content of the webpack configuration file:

const webpack = require('webpack')
const path = require('path')
const ExtractTextPlugin = require("extract-text-webpack-plugin");
const htmlWebpackPlugin = require("html-webpack-plugin");
// console.log(webpack)
var config = {
  //入口文件
  entry: './src/index.js',
  //输出文件配置
  output: {
    //输出文件名
    filename: 'bundle.js',
    //输出文件路径(绝对路径)
    path: '/dist',
    //输出用于指定资源基础路径，当你的应用中的css包含图片的时候，这将非常有用
    // publicPath: '/dist/'
  },
  module: {
    rules: [
      {
        test: /\.css$/,
        use:ExtractTextPlugin.extract({
          fallback: "style-loader",
          use: [
            {
              loader: 'css-loader',
              options:{
                  minimize: true //css压缩
              }
            }
          ]
        })
      },
      {
        test: /\.less$/,
        use: ExtractTextPlugin.extract({
          fallback: 'style-loader',
          use: ['css-loader', 'less-loader'],
          allChunks: true
        })
      },
      {
        //处理js文件或者 react 文件
        test: /\.js|jsx$/,
        use: 'babel-loader',
        exclude: /node_modules/,
      },
      {
        // 处理图片文件/ 可以限制图片大小为多少 转换成base64
        test: /\.(png|jpe?g|gif|svg)(\?.*)?$/,
        loader: 'url-loader',
        options: {
          limit: 7186, // inline base64 if <= 7K
          name: 'static/images/[name].[ext]'
        }
      },
    ]
  },
  plugins: [
    new ExtractTextPlugin({ filename: 'static/app.css', allChunks: true }),
    new htmlWebpackPlugin({
      title: 'react learning',
      template: './src/index.html'
    })
  ]
}

module.exports = config

Is there some configuration that can cover these repeated codes, or can *{} *{} only appear once and package the contents together?

I just started learning, I hope someone with experience can give me some pointers . shoot~

Answer 1

This can be solved with an additional plugin configuration:

https://www.npmjs.com/package...