title: App Engine and Firebase Hosting in One Domain
body: <p>I have a custom domain (<code>travelbox.id</code>) that connected to Firebase Hosting already. I also have an App Engine application to serve as my API. I want to host the App Engine application on <code>api-dev.travelbox.id</code>. I mapped the custom domain to App Engine following <a href="https://cloud.google.com/appengine/docs/standard/nodejs/mapping-custom-domains" rel="noreferrer">this</a> docs but domain connection to Firebase Hosting stop working. If you access <a href="http://api-dev.travelbox.id/" rel="noreferrer">api-dev.travelbox.id</a> it is connected to App Engine. But if you access <a href="https://travelbox.id/" rel="noreferrer">travelbox.id</a> it doesn't connected to Firebase Hosting.</p>
  
  <p>Is that impossible to achieve what I want?</p>