Sync session persistence after server-side credential revocation

The Opera synchronization engine uses an OAuth-based flow to mirror bookmarks, history, and settings across devices. This process relies on a locally stored session token to maintain an authenticated state with the cloud backend.

A potential security gap exists regarding the latency between a password change or session revocation on the Opera account server and the actual termination of the active browser session. If a session is revoked via the account management portal, the local browser instance may continue to operate under the previous token until a specific expiration trigger occurs.

Given the current synchronization architecture, what is the expected timeframe for a revoked session to trigger a re-authentication prompt? Does the browser perform a real-time validity check before each sync operation, or is it dependent on the token's internal TTL?