why is webpack bundling extra files?

This question got answered on Vue Forum so I’m posting the answer here as well

Running

vue inspect --mode production

will show the Webpack configuration that Vue CLI is generating. It ends up with:

entry: {
  app: [
    './src/main.js'
  ],
  activitySubmit: './src/as-setup.js'
}

because as explained in vue docs, the configuration you provide in configureWebpack is merged using webpack-merge, so the default entry is still present.