Firebase Auth Refresh Token Setup

Refresh Token Fix.
Firebase Auth Refresh Token Setup (Bubble + Node.js Cloud Functions)
Description
I need help implementing a reliable Firebase Authentication token refresh system for my web application.
My app currently uses:
Bubble.io frontend
Firebase Authentication
Firebase Cloud Functions (Node.js)
API calls from Bubble to Cloud Functions
Authentication handled through a third-party Firebase plugin in Bubble
The issue I’m facing is ensuring that Firebase ID tokens refresh properly so authenticated API calls to my Cloud Functions continue to work after the initial token expires.
What I Need
Implement a secure refresh token flow
Ensure ID tokens refresh automatically
Allow my Bubble frontend to maintain authenticated sessions
Ensure API calls to Firebase Cloud Functions remain authorized
Provide clear instructions on how the refresh flow works
Tech Stack
Bubble.io (frontend)
Firebase Authentication
Firebase Cloud Functions
Node.js
REST API calls
Google Secure Token endpoint
Ideal Experience
Looking for someone with experience in:
Firebase Authentication
Firebase ID Tokens / Refresh Tokens
Node.js / Firebase Cloud Functions
API integration with Bubble or other no-code platforms
Deliverables
Working refresh token implementation
Explanation of how the system works
Example of how Bubble should call the refresh endpoint
Budget
Open to proposals for a small debugging/setup job.