ERROR in ../../js/webix/webixClass.js 50:11 (Webpack 5.4.0)

При сборке проекта силами webpack'a, при добавлении import { SendServer } from "../../js/webix/sendServer" выскакивает ошибка:

../www-common/www/web/js/webix/webixClass.js 1.97 KiB [built] [code generated] [1 error]

ERROR in ../www-common/www/web/js/webix/webixClass.js 50:11
Module parse failed: Unexpected token (50:11)
You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders
|      * @param def
|      */
>     proper = (obj = {}, name = "", def="")=>{
|         if (obj.hasOwnProperty(name))
|             this[name] = obj[name]
 @ ../www-common/www/web/js/webix/sendServer.js 5:0-40 23:32-42
 @ ./www/web/js/classAdmission.js 3:0-79
 @ ./www/web/js/admission.js 1:0-49 3:31-45
 @ ./www/web/js/index.js 2:0-39 102:32-41

webpack 5.4.0 compiled with 1 error in 427 ms
[webpack-cli] watching files for updates...

Стоит закомментировать импорт и ошибка исчезает.

webpack.mscd.config.js

const       path                 = require("path"),
            HTMLPlugin           = require('html-webpack-plugin'),
            isDev                = process.env.NODE_ENV === 'development',
            isProd               = !isDev,
            {CleanWebpackPlugin} = require('clean-webpack-plugin'),
            WebpackShellPlugin   = require('webpack-shell-plugin'),
            MiniCssExtractPlugin = require('mini-css-extract-plugin'),
            WebpackBar           = require('webpackbar'),
            runtime              = require('babel-plugin-transform-runtime')

const filename = ext => isDev ? `[name].${ext}` : `[name].[hash].${ext}`

const cssLoaders = extra => {
    const loaders = [
        {
            loader:  MiniCssExtractPlugin.loader,
            options: {
                hmr:       isDev,
                reloadAll: true
            },
        },
        'css-loader'
    ]

    if (extra) {
        loaders.push(extra)
    }

    return loaders
}

module.exports = {
    entry:   [
        './www/web/js/index.js'
    ],
    output:  {
        filename:   'bundle.js',
        path:       path.resolve(__dirname, 'www', 'web', 'dist',),
        publicPath: "/dist/"
    },
    module:  {
        rules: [
            {
                test: /\.css$/,
                use:  cssLoaders()
            },
            {
        test: /\.m?js$/,
                exclude: [
                    /\core-js\b/,
                    /\webpack\/buildin\b/,
                    /\node_modules\b/,
                    /\bregenerator-runtime\b/,
                ],
//              use:     {
//                  loader:  'babel-loader',
//          options: {
//            presets: [
//              ['@babel/preset-env', { targets: "defaults" }]
//            ]
//          }
//              },
            },
            {
                test: /\.woff(2)?(\?v=[0-9]\.[0-9]\.[0-9])?$/,
                use:  "url-loader?limit=10000&mimetype=application/font-woff"
            },
            {
                test: /\.(ttf|eot|svg)(\?v=[0-9]\.[0-9]\.[0-9])?$/,
                use:  "file-loader"
            },
        ]
    },
    resolve: {
        modules: [path.resolve('/node_modules')],
        alias:   {
            '@js':          path.resolve(__dirname, 'www/web/js'),
            '@css':         path.resolve(__dirname, 'www/web/css'),
            '@scss':        path.resolve(__dirname, 'www/web/scss'),
            '@sass':        path.resolve(__dirname, 'www/web/sass'),
            '@font':        path.resolve(__dirname, 'www/web/font'),
            '@node_models': path.resolve(__dirname, 'node_models'),
            '@dir':         path.resolve(__dirname),
        }
    },
    plugins: [
        new HTMLPlugin({
                                         inject:     false,
                                         filename:   path.resolve(__dirname, './www/app/themes/1/pages/mscd/dist/index.tpl'),
                                         template:   './www/app/themes/1/pages/index.tpl',
                                         publicPath: "/"
                                     }),
        new HTMLPlugin({
                                         // cache:      false,
                                         // inject:     false,
                                         title:    "APP",
                                         filename: path.resolve(__dirname, './www/web/dist/index.html'),
                                         template: './www/web/html/index.html',
                                         "assets": {
                                             "style": "./css/style.css",
                                         }
                                         // publicPath: "/"
                                     }),
        new MiniCssExtractPlugin({
                                                             filename: filename('css')
                                                         }),
        new CleanWebpackPlugin({dangerouslyAllowCleanPatternsOutsideProject: true}),
        new WebpackBar()
        // new WebpackShellPlugin({onBuildStart:['echo "Webpack Start"'], onBuildEnd:['/bin/bash sync.sh']})
    ],
    devtool: isDev ? 'source-map' : ''
}

package.json:

{
  "name": "...",
  "version": "0.8.0",
  "description": "...",
  "private": true,
  "author": "...",
  "license": "ISC",
  "main": "index.js",
  "directories": {
    "doc": "doc"
  },
  "keywords": [],
  "browserslist": [
    "defaults",
    "Firefox 29",
    "safari 5"
  ],
  "devDependencies": {
    "@babel/core": "^7.12.9",
    "@babel/plugin-proposal-class-properties": "^7.12.1",
    "@babel/plugin-syntax-class-properties": "^7.12.1",
    "@babel/plugin-transform-runtime": "^7.12.1",
    "@babel/preset-env": "^7.12.7",
    "@babel/runtime": "7.12.5",
    "add-asset-html-webpack-plugin": "^3.1.3",
    "babel": "^6.23.0",
    "babel-loader": "^8.2.2",
    "babel-plugin-transform-runtime": "^6.23.0",
    "babel-polyfill": "^6.26.0",
    "babel-preset-es2015": "^6.0.15",
    "babel-preset-es2017": "^6.24.1",
    "babel-preset-stage-0": "^6.24.1",
    "clean-webpack-plugin": "^3.0.0",
    "cross-env": "^7.0.2",
    "css-loader": "^5.0.1",
    "extract-text-webpack-plugin": "^3.0.2",
    "file-loader": "^6.2.0",
    "html-webpack-plugin": "^4.5.0",
    "json-loader": "^0.5.7",
    "mini-css-extract-plugin": "^1.3.1",
    "moment-locales-webpack-plugin": "^1.2.0",
    "node-sass": "^5.0.0",
    "optimize-css-assets-webpack-plugin": "^5.0.4",
    "raw-loader": "^4.0.2",
    "sass": "^1.29.0",
    "sass-loader": "^10.1.0",
    "style-loader": "^2.0.0",
    "twig-html-loader": "^0.1.8",
    "url-loader": "^4.1.1",
    "webpack-cli": "^4.2.0",
    "webpack-dev-server": "^3.11.0",
    "webpack-hot-middleware": "^2.25.0",
    "webpack-shell-plugin": "^0.5.0",
    "webpackbar": "^4.0.0"
  },
  "scripts": {
    "mscdDev": "cross-env NODE_ENV=development webpack --mode development --config webpack.mscd.config.js --progress",
    "mscdDevW": "cross-env NODE_ENV=development webpack --mode development --config webpack.mscd.config.js --watch",
    "mscdPro": "cross-env NODE_ENV=production webpack --mode production --config webpack.mscd.config.js"
  },
  "dependencies": {
    "babel-runtime": "^6.26.0"
  }
}