Outlook web add-in Babel7 RegeneratorRuntime is not defined

Question

I was developing my outlook add-in and everything was working fine, until I used async/await.

I know always get this error: Uncaught ReferenceError: regeneratorRuntime is not defined.

I've researched a lot and found that it was linked to regenerator-runtime/runtime. But when I looked in my webpack configuration, everything that everybody mentioned was already in place.

Here's what I have:

babel.config.json

{
  "presets": ["@babel/preset-env"],
  "plugins": [
    [
      "@babel/plugin-proposal-class-properties",
      {
        "loose": true
      }
    ]
  ]
}

webpack.config.js

/* eslint-disable no-undef */

require("regenerator-runtime/runtime");
const devCerts = require("office-addin-dev-certs");
const CopyWebpackPlugin = require("copy-webpack-plugin");
const HtmlWebpackPlugin = require("html-webpack-plugin");

const urlDev = "https://localhost:3000/";
const urlProd = "https://www.contoso.com/"; // CHANGE THIS TO YOUR PRODUCTION DEPLOYMENT LOCATION

async function getHttpsOptions() {
  const httpsOptions = await devCerts.getHttpsServerOptions();
  return { cacert: httpsOptions.ca, key: httpsOptions.key, cert: httpsOptions.cert };
}

module.exports = async (env, options) => {
  const dev = options.mode === "development";
  const config = {
    devtool: "source-map",
    entry: {
      polyfill: ["core-js/stable", "regenerator-runtime/runtime"],
      taskpane: "./src/taskpane/taskpane.js",
      main: "./src/taskpane/Main.js",
    },
    output: {
      devtoolModuleFilenameTemplate: "webpack:///[resource-path]?[loaders]",
      clean: true,
    },
    resolve: {
      extensions: [".html", ".js"],
    },
    module: {
      rules: [
        {
          test: /\.js$/,
          exclude: /node_modules/,
          use: {
            loader: "babel-loader",
            options: {
              presets: ["@babel/preset-env"],
            },
          },
        },
        {
          test: /\.html$/,
          exclude: /node_modules/,
          use: "html-loader",
        },
        {
          test: /\.(png|jpg|jpeg|gif|ico)$/,
          type: "asset/resource",
          generator: {
            filename: "assets/[name][ext][query]",
          },
        },
      ],
    },
    plugins: [
      new HtmlWebpackPlugin({
        filename: "Main.html",
        template: "./src/taskpane/Main.html",
        chunks: ["polyfill", "main"]
      }),
      new HtmlWebpackPlugin({
        filename: "taskpane.html",
        template: "./src/taskpane/taskpane.html",
        chunks: ["polyfill", "taskpane"]
      }),
      new CopyWebpackPlugin({
        patterns: [
          {
            from: "assets/*",
            to: "assets/[name][ext][query]",
          },
          {
            from: "manifest*.xml",
            to: "[name]" + "[ext]",
            transform(content) {
              if (dev) {
   

         return content;
          } else {
            return content.toString().replace(new RegExp(urlDev, "g"), urlProd);
          }
        },
      },
    ],
  }),
],
devServer: {
  headers: {
    "Access-Control-Allow-Origin": "*",
  },
  https: env.WEBPACK_BUILD || options.https !== undefined ? options.https : await getHttpsOptions(),
  port: process.env.npm_package_config_dev_server_port || 3000,
},


};

  return config;
};

package.json

{
  "name": "office-addin-taskpane-js",
  "version": "0.0.1",
  "repository": {
    "type": "git",
    "url": "https://github.com/OfficeDev/Office-Addin-TaskPane-JS.git"
  },
  "license": "MIT",
  "config": {
    "app_to_debug": "outlook",
    "app_type_to_debug": "desktop",
    "dev_server_port": 3000
  },
  "scripts": {
    "build": "webpack --mode production",
    "build:dev": "webpack --mode development",
    "dev-server": "webpack serve --mode development",
    "lint": "office-addin-lint check",
    "lint:fix": "office-addin-lint fix",
    "prettier": "office-addin-lint prettier",
    "start": "office-addin-debugging start manifest.xml",
    "start:desktop": "office-addin-debugging start manifest.xml desktop",
    "start:web": "office-addin-debugging start manifest.xml web",
    "stop": "office-addin-debugging stop manifest.xml",
    "validate": "office-addin-manifest validate manifest.xml",
    "watch": "webpack --mode development --watch"
  },
  "dependencies": {
    "core-js": "^3.9.1",
    "regenerator-runtime": "^0.13.9",
    "remove-strict-webpack-plugin": "^0.1.2"
  },
  "devDependencies": {
    "@babel/core": "^7.13.10",
    "@babel/preset-env": "^7.12.11",
    "@babel/preset-typescript": "^7.13.0",
    "@types/office-js": "^1.0.180",
    "@types/office-runtime": "^1.0.17",
    "acorn": "^8.5.0",
    "babel-core": "^6.26.3",
    "babel-loader": "^8.2.5",
    "babel-polyfill": "^6.26.0",
    "babel-preset-es2015": "^6.24.1",
    "babel-preset-stage-0": "^6.24.1",
    "copy-webpack-plugin": "^9.0.1",
    "eslint-plugin-office-addins": "^2.0.0",
    "file-loader": "^6.2.0",
    "html-loader": "^2.1.2",
    "html-webpack-plugin": "^5.3.2",
    "office-addin-cli": "^1.3.5",
    "office-addin-debugging": "^4.3.8",
    "office-addin-dev-certs": "^1.7.7",
    "office-addin-lint": "^2.0.0",
    "office-addin-manifest": "^1.7.7",
    "office-addin-prettier-config": "^1.1.4",
    "os-browserify": "^0.3.0",
    "process": "^0.11.10",
    "source-map-loader": "^3.0.0",
    "ts-loader": "^9.2.5",
    "typescript": "^4.3.5",
    "webpack": "^5.50.0",
    "webpack-cli": "^4.8.0",
    "webpack-dev-server": "4.7.3"
  },
  "prettier": "office-addin-prettier-config",
  "browserslist": [
    "ie 11"
  ]
}