Connect your personal extension to Google Drive

Google requires one-time OAuth registration for a personal extension. After setup, connect once in Backup & Restore; Chrome handles token renewal for daily backups.

1. Open Google Cloud Console, create or select your project and enable the Google Drive API.
2. Configure Google Auth Platform branding and audience. Add your own Google account as a test user if the application is in testing. Request only https://www.googleapis.com/auth/drive.appdata. Testing-mode consent can expire; use a suitable publishing status for unattended personal backups.
3. Create an OAuth client of type Chrome Extension. For the Item ID, use the installed extension ID shown in Backup & Restore or chrome://extensions. No client secret is needed.
4. In the project directory, run npm run configure:drive -- YOUR_CLIENT_ID.apps.googleusercontent.com, then npm run build:extension.
5. Reload the existing extension in chrome://extensions. Keep the same directory and extension ID to retain local accounts and access to the same Drive app-data folder. Do not uninstall it.
6. Open Backup & Restore, select Connect Google Drive. If the popup closes during Google sign-in, reopen the extension to check backup status.

The encrypted copies live in the private Drive app-data folder, accessible only to this OAuth application. Google permission is required, but this scope does not grant access to your other Drive files.

To restore on another device, use the same OAuth application/extension ID to recover the encryption key automatically. Download an encrypted local backup before moving or reinstalling the extension.

Sources: Chrome OAuth setup, Google Drive app-data storage.