What problem does this feature solve?

We need to inject environment variables in service-worker.js

process.env.VUE_APP_MY_VAR should be replaced by the DefinePlugin of webpack (automatically configured by Vue CLI) by a value defined in my .env but it works for all files except the "service-worker.js"

My vue.config.js

module.exports = {
  transpileDependencies: [],
  configureWebpack: {
    resolve: {
      symlinks: false
    }
  },
  pwa: {
    workboxPluginMode: 'InjectManifest',
    workboxOptions: {
      swSrc: 'public/service-worker.js'
    }
  }
}

What does the proposed API look like?

I found two obscure solutions for this problem :

The first one : https://stackoverflow.com/a/57051150/4864628

The second (better): https://github.com/diachedelic/vue-cli-plugin-bundle-service-worker

This last solution uses webpack to bundle the service-worker.js file. In my opinion this should be the default behavior of Vue PWA.