power-apps-portals-webpack/webpack.config.js

module.exports = {
  mode: "development",
  module: {
    rules: [
      {
        test: /\.jsx?$/i,
        exclude: /node_modules/,
        use: {
          loader: "babel-loader",
          options: {
            presets: ["@babel/preset-env", "@babel/preset-react"],
          },
        },
      },
      {
        test: /\.css$/i,
        use: ["style-loader", "css-loader"],
      },
    ],
  },
};