How to make an App remember sign status without using Firebase Observer

Hi All, pls I need your direction on the issue I have below.

We use the Firebase Observer to remember that a user has logged in to our App. See below.

firebase.auth().onAuthStateChanged(function (user) {

console.log(‘user in app.js’, user)

if (user != null) {

console.log('check in app.js')

if (user.emailVerified) {

  store.commit('setSignedIn', true)

  store.commit('setDisplayName', user.displayName)

  store.commit('setPhotoURL', user.photoURL)

} else {

  // No user is signed in.

  store.commit('setSignedIn', false)

}

}

})

For some reason, we don’t want to use Firebase Observer anymore to remember user login status.

In the app.vue, the user login status can be determined

computed:{
signed_in() {

  return this.$store.getters.signed_in;
},

}

How can I reference this within app.js?

I tried below but got undefined for signed_in:

if (store.signed_in) {

store.commit(‘setSignedIn’, true)

}

I am opened to any logic that can work to capture user login status within the app.js.

Thanks