Chrome Sync — Privacy Policy

1. Overview

Chrome Sync is a private, production-ready browser extension and sync server designed for syncing bookmarks, open tabs, and installed extension lists across Chromium browser profiles.

Privacy is guaranteed by design through client-side end-to-end encryption (E2EE). The sync server acts strictly as an opaque storage relay and cannot read your bookmark titles, tab URLs, extension lists, or profile names.

2. Information Handled & Encryption Matrix

The table below summarizes all data types processed by Chrome Sync and how they are secured:

Data Category	Content Details	Client Storage	Server Storage State
Tab Snapshots	Open tab titles, URLs, favicons, pinned state	Local Extension State	AES-GCM Encrypted
Extension List	Installed extension names, IDs, versions, status	Local Extension State	AES-GCM Encrypted
Bookmark Data	Bookmark titles, URLs, and folder structures	Local Chrome Storage	AES-GCM Encrypted
Profile Names	Custom browser profile labels (e.g. Work/Personal)	Local Settings	AES-GCM Encrypted
Access Token	Authentication credential (`cs_...`)	Local Extension Storage	SHA-256 Hashed Only
Sync Passphrase	Master secret key for encryption	Local Extension Storage	Never Sent to Server

3. End-to-End Encryption Architecture

Before any sync payload leaves your browser, Chrome Sync encrypts it locally using your secret passphrase:

Key Derivation: Key derived via PBKDF2-SHA256 with 600,000 iterations and a unique server-generated workspace salt.
Cipher: AES-GCM-256 authenticated encryption with cryptographically random 12-byte initialization vectors (IVs).
Authentic Additional Data (AAD): Bound strictly to payload type and client ID to prevent cross-profile payload swapping.

Because encryption occurs exclusively on your device, server operators cannot decrypt your data. If you lose your sync passphrase, server data cannot be recovered by anyone.

4. Data Retention & Automatic Cleanup

Chrome Sync implements strict data minimization:

7-Day Retention Limit: The server automatically purges any sync snapshot or browser profile record that has not been updated within 7 days (1 week).
Manual Deletion: You can instantly clear your local sync settings at any time or request user profile deletion from the server operator.

5. Third-Party Sharing & Compliance

No Data Sales or Advertising: Data is never sold, leased, rented, or shared for advertising, marketing, analytics, or profiling.
No Third-Party Analytics: Chrome Sync contains zero external tracking scripts, google analytics, or third-party telemetry frameworks.
No Remote Code Execution: The extension does not load or execute remote JavaScript code, satisfying all Chrome Web Store developer policies.

6. Contact & Support

For privacy inquiries, security concerns, or account deletion requests, please contact the Chrome Sync maintainer via affan.dev.