Firebase guest auth has "isAnonymus" property set to false in SSR

[greenbeam-ita]

Reproduction

Check snippet below

Steps to reproduce the bug

I'm building my Nuxt 3 App in SSR mode and Firebase auth.
I got an Hydratation issue, don't understand why.
Going trough a deeper inspection detect vuefire do not manage properly firebase guest users.

Simple snippet to in default.vue layout in order to reproduce

<script setup lang="ts">
  import { getAuth, sendSignInLinkToEmail, signInWithEmailAndPassword } from 'firebase/auth'
  import type { MenuItem } from 'primevue/menuitem'
  const currentUser = await getCurrentUser()
  console.log('currentUser', currentUser.uid, currentUser.isAnonymous)

nuxt.config.ts vuefire module configuration

vuefire: {
    auth: {
      enabled: true,
      sessionCookie: true,
    },
    config: {
      apiKey: process.env.FIREBASE_API_KEY,
      authDomain: process.env.FIREBASE_AUTH_DOMAIN,
      projectId: process.env.FIREBASE_PROJECT_ID,
      storageBucket: process.env.FIREBASE_STORAGE_BUCKET,
      messagingSenderId: process.env.FIREBASE_MESSAGING_SENDER_ID,
      appId: process.env.FIREBASE_APP_ID,
    },
    emulators: false,
  },

Expected behavior

I expect to have a proper guest user also in SSR

Actual behavior

From image you can see a mismatch between SSR and client

Additional information

No response

[greenbeam-ita]

I update the issue.
As far as I have session cookie enabled, I check the JWT payload from cookie.

The payload contain correctly the anonymous provider, so in my opinion this is a vuefire bug:

{
  "iss": "https://session.firebase.google.com/cloud2local-f018c",
  "provider_id": "anonymous",
  "aud": "cloud2local-f018c",
  "auth_time": 1742745557,
  "user_id": "ZjQYBs4bm4dHMF8zH3fQIqo4Q7m1",
  "sub": "ZjQYBs4bm4dHMF8zH3fQIqo4Q7m1",
  "iat": 1742746590,
  "exp": 1743178590,
  "firebase": {
    "identities": {},
    "sign_in_provider": "anonymous"
  }
}

[greenbeam-ita]

Anyone can help here?