A chat no longer dies when the network moves under it. A NAT rebind, a lift, a
Wi-Fi radio parking itself, a phone that dozed: the session repairs its own network
path in place, and the messages typed meanwhile go out when it returns.
Recovery is an ICE restart, which renegotiates only the transport path — the DTLS
handshake, the session keys and the SCTP association carrying the data channel all
sit above ICE and survive it. The renegotiation SDP therefore travels over the
existing end-to-end encrypted, SAS-verified channel: no signalling service enters
the design, and an attacker who cannot already decrypt the session cannot inject a
reconnection. A restart is refused outright unless the DTLS fingerprint in the
incoming SDP matches the live session's, so recovery can never re-point a
conversation at a different peer.
When the path is gone for good the session is ended and its data wiped rather than
left half-alive: with no server there is nothing to re-signal through, and a
conversation whose transport is gone should not leave its plaintext in an open tab.
The two cases where that is already certain are recognised in seconds instead of
being retried for two minutes — a channel that has delivered nothing at all since
the drop cannot carry a renegotiation, and an ICE agent left bound to a network that
no longer exists reports zero candidate pairs on every restart.
Judging liveness was the hard part. Silence is not evidence of death: browsers freeze
backgrounded tabs outright, and a frozen peer answers nothing while being perfectly
healthy. What survives that freeze is ICE consent, which the browser runs in its
network stack rather than on the page's thread — so a connected ICE state means a
silent peer is asleep, and only a degraded one turns an unanswered probe into a
teardown. The grace window before a restart is sized to the browser's own timings:
'disconnected' arrives after ~5s of missed consent responses and is held ~25s before
'failed', and that window exists for self-healing, so restarting at the start of it
broke connections that were about to recover.
Several long-standing bugs surfaced along the way and are fixed here:
- handleHeartbeat() was dispatched to but never defined, so every inbound heartbeat
threw a TypeError and peer liveness was never observed at all.
- Heartbeats were folded into the 5-minute maintenance cycle instead of running on
their own timer, far too coarse to notice a dead path.
- ondatachannel can hand over a channel that is already open, so the answering side's
'open' event had been dispatched before the handler was assigned and never fired,
leaving that side with no heartbeat, no watchdog and no file-transfer init. The peer
whose network was fine kept showing "connected" indefinitely because nothing was
running to notice.
- Answering a heartbeat required the peer to have finished verifying, but the two
sides confirm a SAS code at different moments; for that whole window one of them
could not reply and was declared dead on a healthy connection.
- Sending on a channel that was not ready returned in silence: the text stayed in the
box, nothing was transmitted, and nothing said why.
- The send path gated on navigator.onLine and the offline/online events, which report
whether an interface exists rather than whether anything is reachable. A tab the OS
froze misses the 'online' edge, and this side then queued every message forever: one
tick on everything it sent, while incoming messages kept arriving. Sending is now
decided by the data channel, and queues drain by polling rather than on an edge, so
a missed event cannot strand them.
- A false offline modal appeared on a working session, because the offline event was
taken at face value.
tests/session-recovery.test.mjs covers the state machine, the backoff and its
serialisation, the offline hold, the sleeping-peer discriminator and the identity
check.
Ground-up visual redesign across the entire surface (landing, connection
setup, chat header, security verification report, file transfer, PWA
install/update/offline dialogs).
Offline reworked: store-and-forward queue (send while offline → queued,
delivered on reconnect), WhatsApp-style per-message delivery status
(sending/sent/delivered/not-sent) via delivery receipts, offline buffering
for messages to an offline peer, and offline state no longer leaking into
the connection indicator. Resilient chunked file transfer with retransmission
and auto-save. README + screenshots added.
- Disable timer-based key rotation for Double Ratchet mode
- Auto-reinitialize encryption keys when missing but ECDH available
- Preserve active keys during periodic cleanup in ratchet sessions
- Fix IndexedDB "database closing" errors with connection checking
- Add individual transactions per queue item to prevent race conditions
- Added SecureNotificationManager with cross-browser support (Chrome, Firefox, Safari, Edge)
- Integrated WebRTC message notifications with tab visibility detection
- Implemented XSS protection, URL validation, and rate limiting
- Notifications shown only when chat tab is inactive
- Enforced HTTPS and user gesture requirements
- Removed temporary console logs used for debugging
- Disabled DEBUG_MODE flag
- Updated configuration to run in production mode
- Cleaned up leftover debug utilities to reduce noise in console
Replace CDN React/ReactDOM/Babel with local libs; remove Babel and inline scripts
Build Tailwind locally, add safelist; switch to assets/tailwind.css
Self-host Font Awesome and Inter (CSS + woff2); remove external font CDNs
Implement strict CSP (no unsafe-inline/eval; scripts/styles/fonts from self)
Extract inline handlers; move PWA scripts to external files
Add local QR code generation (qrcode lib) and remove api.qrserver.com
Improve SessionTypeSelector visual selection (highlighted background and ring)
Keep PWA working with service worker and offline assets
Refs: CSP hardening, offline-first, no external dependencies
- Replace unsafe console.error/warn calls with secure logging system
- Implement production-safe logging that masks sensitive data
- Add automatic sanitization for cryptographic keys and sensitive information
- Create secure logging infrastructure for EnhancedSecureWebRTCManager and EnhancedSecureCryptoUtils
- Prevent data leakage of internal logic and error details in production
- Add production/development mode detection for appropriate logging levels
- Implement server-side error logging for production environments
- Improve installation status detection logic
- Add proper DOM cleanup when PWA is installed
- Enhance monitoring for installation state changes
- Fix shouldShowPrompt() logic to always check current status
- Add forceInstallationCheck() method for manual status updates
- Improve installation status detection logic
- Add proper DOM cleanup when PWA is installed
- Enhance monitoring for installation state changes
- Fix shouldShowPrompt() logic to always check current status
- Add forceInstallationCheck() method for manual status updates
- New users now see install prompt automatically after 10 seconds
- Smart cancellation prevents duplicate prompts
- Added PWAUtils methods for delayed prompt management
- Enhanced user onboarding experience
- Respects installation status and user preferences
- Added a real verification system for active encryption modules, giving users full control over enabled modules.
- During session purchase or activation, the actual enabled modules are now displayed for both free and paid sessions.
- Refactored session timer initialization for proper functionality and accurate countdown.
- Optimized code structure related to session management and module verification.
- Add manifest.json with full PWA configuration
- Support for installation on all platforms (iOS, Android, Desktop)
- Custom app icons (72x72 to 512x512) with maskable support
- App shortcuts for quick actions (Create/Join Channel)
- Protocol handlers for web+securebit:// links
- Share target integration
- Implement enhanced Service Worker (v4.0)
- Smart caching strategies (cache-first, network-first, stale-while-revalidate)
- Security-aware caching (excludes sensitive endpoints)
- Background sync for failed requests
- Offline fallbacks with custom error handling
- Response cloning fixes and CORS handling
- Add PWA Install Prompt Manager
- Cross-platform install detection and prompts
- iOS Safari specific installation guide
- Smart dismissal logic with retry mechanisms
- Install success notifications and user guidance
- Persistent install preferences with localStorage
- Implement comprehensive Offline Manager
- IndexedDB for offline data persistence
- Automatic message queuing and sync when online
- Session state recovery after connection loss
- WebRTC reconnection handling
- Real-time connection status indicators
- Offline guidance and help system
- Add offline-first features
- Message queue with priority and retry logic
- Session data preservation during disconnection
- Application state recovery
- Background sync registration
- Periodic cleanup of old offline data
- Enhanced user experience
- Connection status notifications
- Offline mode guidance and help
- Automatic sync notifications
- Reconnection progress indicators
- Platform-specific installation instructions
This implementation ensures SecureBit.chat works seamlessly offline while maintaining security and providing a native app-like experience across all platforms.
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