I\'m a pretty new programmer going through the Firebase tutorial. I have gone through steps 1-5 of the tutorial (https://codelabs.developers.google.com/codelabs/firebase-web
In my case firebase was using the wrong directory, also see here: firebase CLI didn't recognize the current project directory for 'firebase init'. While I was expecting firebase to put all created files into my project directory it was totally disconnected and put all files into my /Users/MyUserName directoy and deploying the wrong index.html from there.
This is how to fix it (no reinstall of firebase needed as suggested in the linked post):
By the way, for everyone who is using Angular 7, this tutorial about deploying an angular 7 app to firebase hosting was really helpfull to me.