When webpack4.x is packaged

when webpack4.x is packaged in require b.js in a.js, what happens when css introduced in b.js is packaged into css introduced by a.js?
the following is the webpack.config.js configuration
Please give us your advice

const path = require("path");
const htmlWebpackPlugin = require("html-webpack-plugin");
const cleanWebpackPlugin = require("clean-webpack-plugin");
const MiniCssExtractPlugin = require("mini-css-extract-plugin");//css
const ExtractTextPlugin = require("extract-text-webpack-plugin");


var getHtmlConfig = function (filename,title) {
    return {
        template:"./src/" + filename + "/"+ filename + ".html",
        filename: filename + ".html",
        title:title,
        hash:true,
        chunks:[filename]
    }
}
module.exports = {
    entry: {
        index:"./src/index/index.js",
        test:"./src/test/test.js"
    },
    output: {
        filename: "./js/[name].bundle.js",
        path: path.resolve(__dirname,"dist"),
    },
    devServer:{
        contentBase: "./dist"
    },
    plugins: [
        new htmlWebpackPlugin(getHtmlConfig("index","index")),
        new htmlWebpackPlugin(getHtmlConfig("test","test")),
        new cleanWebpackPlugin(["dist"])
    ],
    module:{
        rules:[
            {
                test:/\.css$/,
                use:ExtractTextPlugin.extract({
                    fallback: "style-loader",
                    use: "css-loader"
                })
            },
            {
                test:/\.(png|svg|jpg|gif)$/,
                use:[
                    "file-loader"
                ]
            },
            {
                test: /\.(woff|woff2|eot|ttf|otf)$/,
                use:[
                    "file-loader"
                ]
            }
        ]
    }
Nov.02,2021
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b3c0b0-2c2c4.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b3c0b0-2c2c4.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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