Telegram Drive v2.5.1

Sponsor Banner Reliability

• Restored sponsor artwork in the desktop banner when an embedded WebView does not reliably paint the provider’s nested frame.
• Confirms the 300 × 250 creative image has loaded before displaying it, while retaining the isolated sandbox, popup blocking, and unsafe-eval protection.
• Keeps the existing 10-second countdown, manual dismissal, and 45-minute return interval unchanged.

Encrypted Settings Sync

• Added opt-in, manual cross-device settings sync through the user’s own Telegram Saved Messages with no Telegram Drive sync server.
• Protects synced preferences with Argon2id and authenticated XChaCha20-Poly1305 encryption using a user-provided passphrase that is never stored or uploaded.
• Restricts sync to an explicit allowlist of portable preferences. Credentials, API and WebDAV keys, proxy details, supporter activation, crash consent, and file data are never included.
• Added confirmation before replacing a backup from another device or applying downloaded preferences.

Offline Files and Windows Cache Reliability

• Made recently viewed plaintext preview files use true least-recently-used retention, so actively reopened files are not evicted ahead of stale files.
• Added actionable offline-cache inspection and cleanup errors instead of leaving Storage settings in an indefinite loading state.
• Fixed Windows Transcode Cache commands to use the application’s managed shared cache state consistently.

Japanese Language Support

• Completed the Japanese application translation and added Japanese locale registration, resolution, fallback, and CJK visual regression coverage.
• Strengthened localization validation with locale-specific invariant handling and zero copied-English baseline debt for Japanese, Italian, and Vietnamese.

Supporter Experience

• Ensures verified ad-free users never begin loading sponsor content while entitlement status is being checked.
• Licensed users skip supporter promotion pages. Unlicensed desktop users receive a clear optional $5 lifetime ad-free offer at most once on app launch every 24 hours.
• Clarified throughout the application and supporter terms that every feature remains free and the supporter license only removes sponsor placements.
• Preserves the existing activation, recovery-code, device-limit, update, and refund/reversal safeguards.

Verification

• Production frontend build and complete frontend regression suite passed.
• Complete desktop Rust test suite passed with only the existing live advertisement network test ignored.
• Localization structure, variables, invariant, and type validation passed.