KoalaSync/docs/CHANGELOG.md

# KoalaSync Changelog

All notable changes to the KoalaSync browser extension and relay server.

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## [v3.0.0] — 2026-07-26

### Added
- **Extension: Optional encrypted room chat** — Rooms now support live-only, end-to-end encrypted text messages. Chat is disabled and hidden by default and can be enabled explicitly in the extension options.
- **Extension: Persistent room chat key** — Every room generates and retains a chat key even while chat is disabled, so chat can be enabled later without creating a new room.
- **Extension: Floating player chat** — When enabled, chat is available from a floating control over the selected player and opens in an overlay without replacing the synchronized video.
- **Extension: Dedicated chat settings** — Chat now has its own settings section for enablement, left/right/free-floating placement, compact/standard/large/custom sizing, and bubble-versus-open startup behavior.

### Security
- **Ciphertext-only relay** — The relay receives and forwards encrypted message payloads without storing chat history or accepting client-supplied plaintext, sender identities, timestamps, or message IDs as authoritative.
- **Backward-compatible rollout** — Versioned `chat-v1` capabilities ensure old non-chat extensions never receive unknown chat events, while current extensions continue to work with older chatless relay versions.

### Changed
- **Build dependencies** — Updated the supported build and validation toolchain and refreshed compatible transitive dependencies.
- **Relay container runtime** — Moved the production container from end-of-life Node.js 20 to Node.js 24 LTS and made production dependency installation deterministic with `npm ci --omit=dev`.

## [v2.6.4] — 2026-07-16

### Changed
- **Extension: Localized store metadata** — Renamed the public extension title to `Watch Party - KoalaSync` and added natural, store-ready descriptions for all 15 supported locales while preserving regional language variants.
- **Extension: Locale-based manifest metadata** — The extension name and description now resolve through Chrome/Firefox `_locales` messages instead of being hardcoded in the manifest.

### Fixed
- **Build: Extension metadata validation** — Extension builds now fail clearly for invalid locale JSON, missing metadata, an incorrect extension title, or store titles and descriptions that exceed their character limits.

## [v2.6.3] — 2026-07-15

### Fixed
- **Extension: Host-access recovery races** — Prevents stale permission grants, reinjection retries, closed tabs, and rapid target changes from reactivating or clearing the wrong video tab.
- **Extension: Cross-browser host patterns** — Uses Firefox-compatible match patterns for local servers while preserving exact Chromium port scopes.
- **Extension: Force-sync target integrity** — Keeps sampled playback time and acknowledgements bound to the selected tab during recovery and target changes.

## [v2.6.2] — 2026-07-15

### Added
- **Website: Site-access recovery guide** — Added an English help page and a localized banner across every landing-page language.

### Fixed
- **Extension: Withheld website access recovery** — Detects browser-withheld host access, shows a localized allow-access action, requests only the selected website origin, and resumes the selected tab after access is granted.
- **Extension: Target-tab reliability** — Hardened permission recovery against rapid tab changes, navigation, closed tabs, service-worker restoration, and stale pending state.
- **Browser compatibility** — Uses Chrome's toolbar access request only when available, with a direct user-gesture permission fallback for Firefox and older Chromium browsers.

---

## [v2.6.1] — 2026-07-15

### Fixed
- **Extension: Episode Lobby peer list** — Peer names in the lobby are now rendered as text instead of markup. A peer could previously put HTML in their username and have it rendered in everyone else's popup, which allowed loading remote images (leaking viewer IP addresses) and spoofing the readiness badges. Scripts were already blocked by the extension's content security policy.

### Changed
- **Release checks: AMO validation** — `npm run verify` now runs Mozilla's `addons-linter` against the built Firefox artifact with `--warnings-as-errors`, and ESLint enforces `no-unsanitized`, so upload-blocking issues surface locally instead of at submission time.

---

## [v2.6.0] — 2026-07-15

### Added
- **Extension: Appearance controls** — Added localized system, light, and dark theme options with an early theme initializer to avoid flashes during popup startup.

### Changed
- **Extension: Popup and settings redesign** — Unified controls, status surfaces, colors, icons, badges, and accessibility behavior; settings are now organized into mutually exclusive accordion groups.

### Fixed
- **Extension: Episode Lobby reliability** — Prevented the lobby from remaining stuck in a loading state and stopped episode transitions from triggering on non-episodic media.
- **Extension: Tab-title normalization** — Notification counters such as `(14)`, `[7]`, and `(99+)` are removed reliably without stripping legitimate large numeric titles.

---

## [v2.5.4] — 2026-07-08

### Changed
- **Extension: Refined clutter blacklist** — Removed `localhost` and cloud storage providers (`drive.google.com`, `dropbox.com`, `onedrive.live.com`, `icloud.com`) from the domains blacklist so that local web development servers and tabs hosting video files in cloud storage are no longer hidden under "Hide Clutter Tabs".

---

## [v2.5.3] — 2026-07-02

### Fixed
- **Extension: Disney+ force sync and seeking** — Fixed force sync on Disney+ failing or jumping to wrong positions. The extension now relies solely on accurate player-API time and fails cleanly when it isn't available yet, instead of falling back to unreliable raw video data.
- **Extension: Force-sync accuracy** — When syncing to the group, peers whose current position isn't known yet (e.g. a Disney+ peer that just loaded) no longer pull the sync target toward the start of the video.
- **Extension: Disney+ Host Control Mode** — Regular Disney+ content is no longer misclassified as a live stream, which had silently disabled the desync dialog and snap-back for guests in host-controlled rooms. YouTube and Twitch live detection is unchanged.
- **Extension: Disney+ episode auto-sync** — Episode transitions and the "waiting for peers" lobby flow now work reliably on Disney+ again.

---

## [v2.5.2] — 2026-07-02

### Added
- **Extension: Privacy title controls** - Advanced users can now disable sending browser tab titles separately from media titles. Media titles can still be sent in full, reduced to detected episode identifiers such as `S01E04`, or hidden entirely. Defaults remain full titles for backwards compatibility.
- **Relay: Cleaner restart handling** — Connected clients are now disconnected explicitly during relay shutdown so reconnects recover more predictably.
- **Relay: Stronger abuse protection** — Rapid room-leave spam is now rate-limited.
- **Extension: Hidden remote seek diagnostics** — KoalaDev can use the hidden Dev tab to simulate remote seeks and inspect precise native/page-API timing while debugging playback integrations.

### Changed
- **Extension: Shared page-API seek bridge** — Netflix and Disney+ now use a common page-level seek bridge so private player APIs can be invoked from the page context while the default HTML5 path stays unchanged.
- **Build: Release build timestamp** — Extension builds now inject a build timestamp into the hidden Dev tab for easier local package verification.

### Fixed
- **Extension: Disney+ precise sync** — Disney+ now reads time and seeks through the real page media-player API, and the temporary DOM timeline/button scraping fallback has been removed.
- **Extension: Netflix seek reliability** — Netflix seeking keeps using the page player API with a safer session lookup path.
- **Extension: Tab-title counter cleanup** — Leading browser notification counters such as `(14)` or `[7]` are removed from shared tab titles and matching logic without changing the existing privacy controls.
- **Extension: Tab navigation reinjection** — Reinjecting the content script after selected-tab navigation now uses the same page-API-aware injection path.

---

## [v2.5.0] — 2026-06-29

### Added
- **Extension + Relay: Host Control Mode** — Room owners can now switch a room between open playback control and host-controlled playback. In host-only mode, guests stay synchronized but their local play, pause, and seek actions are not rebroadcast to the room.
- **Backward-compatible Host Control rollout** — The extension only shows Host Control when the connected relay supports it, so users on older self-hosted servers do not see controls that cannot work yet.
- **Extension: Clear host and guest states** — The popup shows the current control mode, host status, peer roles, and localized guest guidance so participants understand when playback is controlled by the host.
- **Website: FAQ clarification for streaming access** — The landing page and FAQ structured data now state clearly that KoalaSync does not stream, host, share, or bypass access to video content. Every participant watches locally and needs their own access to services such as Netflix.

### Changed
- **Playback sync now follows the room's control setting** — When Host Control is enabled, only the host can drive room-wide playback changes; guests can still watch in sync without accidentally changing playback for everyone.

---

## [v2.4.6] — 2026-06-23

### Fixed
- **Room and settings are no longer stored in `chrome.storage.sync`** — Room ID, password, and username were being resurrected from synced storage on a fresh install (sync survives an uninstall in the user's Google account), which made the extension silently auto-connect to a dead room and appear permanently connected. `getSettings()` and all settings reads are now local-only, and legacy keys are actively purged from sync on install/update/startup. Only `onboardingComplete` and `dismissedHints` remain in sync.
- **No server traffic while alone in a room** — When you are the only peer, heartbeats, force-sync, and episode auto-sync are now fully suppressed (previously the keepAlive heartbeat, force-sync, and episode lobby were still broadcast to an empty room). The solo state is re-evaluated live on every event — never cached — so the instant another peer joins, syncing resumes immediately, including an instant state push so the newcomer sees your current position without waiting for the next heartbeat.

## [v2.4.4] — 2026-06-23

### Changed
- **Server: Event rate limit raised 30 → 50 per 10s**, and all connection/event/health rate-limit thresholds and windows extracted into named constants.
- **Extension: Reconnect backoff tuned and jittered** — capped at ~8 attempts/60s (under the per-IP connection limit) with ±20% jitter to de-synchronize reconnect herds after a server blip.
- **CI: Added a verification workflow** running lint, tests, audits, and builds on every push/PR; the release build now uses `npm ci`.

### Fixed
- **Extension: Offline event-queue flush is now paced** (small batches instead of one synchronous burst) so a reconnect after a long outage no longer trips the server event limit and gets disconnected on rejoin.
- **Extension: Ping liveness tolerates one missed PONG** — a reconnect is forced only after 2 consecutive misses (~20s) instead of a single 5s timeout, avoiding spurious drops under transient load.
- **Extension: `socket.send()` failures are caught and re-queued** instead of losing the event on a disconnect race.

## [v2.4.3] — 2026-06-19

### Added
- **Two new languages: Ukrainian (`uk`) and Chinese (`zh`, Simplified)** — added across the extension (UI strings + Chrome `_locales`) and the website (localized pages, hreflang/Open Graph/schema tags, language selector), bringing the total to 15 languages.

### Changed
- **Play/pause sync coalescing** — The content script now collapses rapid bursts of native play/pause events (source swaps, ABR/quality switches, ad transitions, page teardown) into a single relayed command: the first event is sent instantly and a short 150ms window absorbs the rest. This cuts redundant relay traffic and stops bursts from tripping the server's per-socket event rate limit.

### Fixed
- **zh/uk translation quality** — Corrected systematic machine-translation word-sense errors in the two new locales (e.g. "Play", "Status", "Leave Room", "Clear", "Open", "peers", and audio compressor terms) and translated the remaining English leftovers.
- **Relay logging** — An `EVENT_ACK` aimed at a peer that already left is now logged quietly instead of as a `[SECURITY]` cross-room event, so genuine cross-room attempts stand out in the logs.

## [v2.4.2] — 2026-06-19

### Changed
- **Extension: Optimized uninstall URL registration** — Extracted registration into a reusable, race-condition-protected `initUninstallURL()` helper. It registers the uninstall feedback URL with browser context on both extension installation/update and browser startup to prevent state loss, without storing or sending an installation token.

## [v2.4.1] — 2026-06-19

### Added
- **Extension: Onboarding tour now has a closing step** — The first-run tour ends on a dedicated "You're all set!" card (the `ONBOARDING_5` copy that already existed in all 13 locales but was never shown). The tour no longer stops abruptly on the username step.
- **Extension: One-click invite from the empty peer list** — The "No peers yet" state now shows a **📋 Invite Link** button that copies the invite link to the clipboard, so users can share it without hunting for the field.

### Changed
- **Extension: Cleaner onboarding welcome** — Step 1 is now a centered welcome card instead of spotlighting the logo title. Added a guard so target-less tour steps center cleanly.
- **Website: Mobile comparison table** — The KoalaSync vs Teleparty table stacks into per-feature cards on phones instead of forcing horizontal scrolling; feature descriptions are shown again on mobile.

### Fixed
- **Extension: Onboarding step counter/progress placeholders** — Static `Step 1 of 3` / 33% fallbacks in `popup.html` corrected to match the actual 5-step tour (`Step 1 of 5` / 20%).
- **Website: Mobile navigation restored** — The header hamburger menu was hidden by a `display:none !important` rule, leaving the nav links unreachable on phones. Re-enabled, with spacing kept comfortable down to ~320px.
- **Website: Hero alignment on mobile** — A fixed-width extension mockup forced the hero grid column wider than the container, shifting all hero content off-center (larger left margin than right). The mockup is now responsive (`width:100%/max-width` + `minmax(0,1fr)` grid track).
- **Website: Reveal-animation fallback** — Added a `<noscript>` style fallback and `IntersectionObserver` feature guards so scroll-revealed content can never stay invisible if JavaScript is disabled or unsupported.

## [v2.4.0] — 2026-06-16

### Added
- **Extension: Lazy WebSocket connection** — The extension no longer maintains a permanent WebSocket connection to the relay server. Instead, the connection is established only when actively in a room or when the popup is opened with a saved room configuration. This improves privacy (IP is not exposed while idle), reduces battery/network usage, and prevents the server from tracking online status of inactive users. Automatic reconnect is guaranteed while in a room — zero behavior change during active sync sessions. See `connectIntent` flag in `background.js`.
- **Extension: Episode title regex unification** — `extractEpisodeId()` had inconsistent regex patterns between `background.js` and `content.js`. The content script correctly matched Crunchyroll-style separators (`S01/E01`) while the service worker's stricter pattern (`[\s\-\.]*`) silently rejected them, causing episode lobby sync failures. Now unified to `[^a-zA-Z0-9]*` via shared `episode-utils.js`.
- **Unit tests: `rate-limiter` and `episode-utils`** — 12 test groups for rate-limit functions and 30+ assertions for episode title parsing, covering all 6 separator types (dash, dot, slash, colon, comma, space). Run automatically via `npm run verify`.

### Changed
- **Server: Rate limiter extracted to `rate-limiter.js`** — 6 rate-limit functions, all rate-limit Maps, and cleanup intervals moved from `index.js` (149 lines). `index.js` now imports via facade pattern with re-exports for backward compatibility.
- **Extension: Episode utilities extracted to `episode-utils.js`** — `extractEpisodeId()` and `sameEpisode()` deduplicated from `background.js` and `content.js`. The shared module is imported as an ES module by the service worker and injected into the content script IIFE by the build script.
- **Build: `"type": "module"` in root `package.json`** — All scripts standardized to ESM (`.mjs`) or explicitly CommonJS (`.cjs`). Eliminated Node.js `MODULE_TYPELESS_PACKAGE_JSON` warnings.
- **Build: 4 CJS scripts renamed to `.cjs`** — `build-extension.js`, `test-content-video-finder.js`, `test-locales.js`, `website/build.js`.

### Fixed
- **Server: npm audit resolved** — `ws` package vulnerability (CVE-2024-37890) fixed. Zero vulnerabilities in production dependencies.
- **Pop-up: Connection status flicker fixed** — Removed hardcoded `disconnected` state on every pop-up open. Status now reflects actual background state from the first frame.
- **Pop-up: Join button timeout improved** — No longer blindly re-enables after 15s. Polls connection status and extends window if still connecting.
- **Pop-up: Validation failure state cleanup** — Custom server URL validation errors now properly reset `isProcessingConnection` and `joinBtnTimeout`.
- **Extension: `WEB_JOIN_REQUEST` channel leak fixed** — Missing `sendResponse()` call when already in the target room.
- **Extension: `LEAVE_ROOM` now clears `roomId` from storage** — Prevents phantom auto-reconnect on browser restart after explicit leave.
- **Extension: Reconnect attempt counters reset on leave** — Prevents stale `reconnecting` status display after intentional disconnect.

## [v2.3.2] — 2026-06-16

### Changed
- **Extension: Refined Spanish, Italian, and Portuguese translations**: Complete manual review and improvement of all Spanish (`es`), Italian (`it`), Portuguese — Brazil (`pt-BR`), and Portuguese — Portugal (`pt`) locale files for both the extension UI and the landing website. Thanks to [@Kaia-Alenia](https://github.com/Kaia-Alenia) for the native-quality translations.

### Fixed
- **Extension: Locale typos and corrupted characters fixed**: Repaired a Korean refresh button label (`Refreschi` → `새로고침`), a corrupted Korean connection status string (`연kel` → `연결`), a Korean character contaminating a Japanese string (`의` → `の`), and a Dutch typo (`cmmuniceren` → `communiceren`).
- **Server: Admin token length leak fixed (timing side-channel)**: `isAdminMetricsAuthorized()` returned early when the provided buffer had a different length than the expected token, leaking the token length via response timing. Now `crypto.timingSafeEqual` runs in constant time on every attempt regardless of length match. Reported by [@Kaia-Alenia](https://github.com/Kaia-Alenia).

---

## [v2.3.1] — 2026-06-15

### Fixed
- **Server: Concurrent peer join race condition and teardown error handling**

### Changed
- **Server: Smart unhandled rejection handling (exits after 5/min instead of 1)**
- **Server: Optimized admin health metrics allocation**

---

## [v2.3.0] — 2026-06-14

### Added
- **Extension: New Interactive Onboarding Tour**: A fully redesigned, interactive step-by-step onboarding experience.
- **Extension: Auto-Switch to Sync Tab**: The UI now intelligently switches to the Sync tab when you join a room to guide video selection.
- **Extension: Uninstall URL Integration**: Prepared an uninstall URL setup that works natively across Chrome and Firefox, cleanly attaching browser context for analytics.

### Fixed
- **Extension: Infinite Seek Loop Prevention**: Replaced the fragile time-based seek suppression with an exact target-time verification mechanism, entirely eliminating infinite seek loops on slow buffers.
- **Extension: Zombie Connections Resolved**: Implemented a forced disconnect upon ping timeouts, ensuring the extension reliably auto-reconnects when the WebSocket hangs in a half-open state.
- **Extension: Room Switching Architecture**: Joining a new room while already connected now explicitly severs the old connection first, preventing state cross-contamination. 
- **Extension: Join/Leave Race Conditions**: Added UI locks to prevent users from accidentally sending conflicting connection commands via rapid double-clicking.
- **Extension: Same-Room Invite Bypass**: Clicking an invite link for the room you are currently in no longer triggers a redundant reconnect, instead instantly confirming the join.
- **Extension: Audio settings now propagate immediately to video tabs**: Changes made in the audio options page are now instantly applied to the active video tab. Previously, settings saved to `chrome.storage.local` were not picked up by the background listener, which only watched `chrome.storage.sync`.
- **Extension: Audio compressor now logs enable/disable state and resume failures**: The compressor reports when it is activated or bypassed, and warns if the `AudioContext` cannot be resumed (e.g. browser autoplay policy requires a user gesture on the page first).
- **Extension: Video heartbeat no longer sent when alone in a room**: The full media metadata `PEER_STATUS` is now only emitted when other peers are present. The session keepalive (background heartbeat) continues to run unaffected, preventing the server reaper from disconnecting idle peers.
- **Server: Increased `failedAuthAttempts` eviction threshold from 50k to 200k**: Reduces frequency of expensive batch evictions under high auth-failure volumes, smoothing heap usage.

---

## [v2.2.4] — 2026-06-10

### Fixed
- **Extension: Error notifications now respect `browserNotifications` setting**: Server error events (e.g. "Server is restarting") no longer trigger a browser notification when the user has disabled notifications in the extension settings.
- **Server: Misleading reconnect message corrected**: The graceful shutdown message no longer tells users to manually reconnect — the extension handles this automatically.

---

## [v2.2.3] — 2026-06-10

### Added
- **Artifact Attestations (Supply Chain Security)**: All release artifacts (Docker images, extension ZIPs) are now published with signed [SLSA provenance attestations](https://docs.github.com/en/actions/how-tos/secure-your-work/use-artifact-attestations) via `actions/attest@v4`. Anyone can verify that an artifact was built from this repository using `gh attestation verify`.
- **Admin health: `rateLimits.denied` counters**: New rolling counters track actual rate-limit denials (429 responses), separate from `rateLimits.trackedClients` which reports unique IPs in the tracking window.
- **Docker HEALTHCHECK**: Container health is now checked every 30s via `GET /health`.
- **`npm start` script**: Server can now be started with `npm start`.

### Fixed
- **Server: `activeLobby` no longer silently overwritten**: If a second peer sends `EPISODE_LOBBY` while a lobby is already active, the request is now ignored instead of destroying the first peer's lobby.
- **CORS log sanitization**: Rejected origin headers are sanitized (`\r\n` stripped) to prevent log injection.
- **Extension: pagehide resource leak**: `keepAlivePort`, `lobbyPollTimer`, heartbeats, and `MutationObserver` are now properly cleaned up when a tab is hidden or enters bfcache.
- **Extension: unhandled storage rejections**: `chrome.storage.session.set()` calls in the disconnect handler now have `.catch(() => {})`.
- **`'Pixel'` duplicate in name generator**: Second occurrence replaced with `'Nitro'` for better name diversity.
- **`'opposum'` typo**: Corrected to `'opossum'` in the emoji map and added `'Opossum'` to `USERNAME_NOUNS`.
- **Test reliability**: `test-server-routes.mjs` now sets `ADMIN_METRICS_TOKEN` before importing the server module, fixing standalone test execution.
- **`MAX_PEERS_PER_ROOM` konsistent**: `.env` auf 25 gesetzt (wie `.env.example`).
- **pt-BR.json duplicate removed**: Duplicate `FOOTER_DISCLAIMER` key removed from website locale.

### Changed
- **Admin health: `rateLimitEntries` renamed to `rateLimits.trackedClients`**: The field now accurately describes that it tracks unique clients in the rate-limit window, not denial counts. Update your json_exporter/Grafana config accordingly.
- **README restructured**: Sections reordered by progressive technical depth. New "Supply Chain Security" subsection under "For Developers & Self-Hosters" with verification commands.

---

## [v2.2.2] — 2026-06-09

### Added
- **Chrome Web Store i18n Support**: Added `default_locale: "en"` to manifest and created `_locales/*/messages.json` for all 13 supported languages. This unlocks the language selection dropdown in the Chrome Web Store dashboard, allowing translated store listings (title, description) per locale. The extension's own UI translations (`locales/*.json` + `i18n.js`) remain unchanged.
- **Locale test coverage**: Extended `scripts/test-locales.js` to validate all `_locales/*/messages.json` files (correct format, required keys, no duplicates) and verify `default_locale` is set in the manifest.

### Fixed
- **Copy Logs button alignment**: Removed stray `margin-top: 8px` inherited from `.secondary` class that pushed the button 8px down in the connection status row.

---

## [v2.2.1] — 2026-06-09

### Added
- **Server Ping Display**: Measures round-trip latency to the relay server via application-level ping/pong events. The extension sends `PING { t }` every 15 seconds; the server responds with `PONG { t }`. Round-trip time is calculated client-side and displayed in the Status tab, color-coded (<50ms green, 50–150ms yellow, >150ms red). No ping value is shown when disconnected or if the server does not respond within 5 seconds.
- **Peer Ping Response (Future-Proof)**: The extension can now respond to incoming `PING { t, sender }` events from other peers by sending back `PONG { t, target: sender }`. The relay server forwards `PING` to the target peer and routes `PONG` back to the original sender. Both client and server validate that peers are in the same room before forwarding/routing. Peer-to-peer ping initiation will be activated in a future extension update without requiring a server restart.

---

## [v2.2.0] — 2026-06-08

### Added
- **Web Audio API Compressor**: Built-in audio dynamic range compression with four presets (Recommended, Dynamic Range, Vocal Enhancement, Smooth) and fully customizable sliders (threshold, ratio, knee, attack, release). Uses dry/wet crossfade (40ms linear ramp) to avoid clicks. Configured via the new Audio Options page accessible from the Settings tab.
- **Audio Options Page** (`audio-options.html`): Dedicated settings page with master toggle, compressor preset selector, real-time custom sliders, and equalizer placeholder. Dark theme matching the popup design.
- **Feature Hint System**: Generic `dismissedHints` array in sync storage for announcing new features. First hint highlights the Audio Options entry in Settings. Extensible for future features.

### Changed
- **Support Links**: Static footer badges on the Settings and Status tabs linking to the developer's support page. README and website footer updated with a Support KoalaSync badge.

### Fixed
- **Portuguese (PT) locale**: Removed Italian contamination — "sincronizzazione" → "sincronização", "tempo reale" → "tempo real", "Link di Invito" → "Link de Convite", "Sair della Sala" → "Sair da Sala".
- **Korean locale**: Fixed broken character in `HOWTO_STEP_2_TEXT` (`클rip보드` → `클립보드`).
- **Website COMP_FEAT_6_KOALA**: Normalized from inconsistent "6 Languages" to "13 Languages" across all locale files (en, de, es, fr, pt-BR, ru).
- **Debug report showing wrong logs**: Fixed `logs.slice(-50)` and `history.slice(-20)` in the "Copy Debug Report" feature. Since `addLog()` and `addToHistory()` use `unshift` (inserting entries at index 0), the arrays are ordered newest-first. `slice(-N)` took the N **oldest** entries instead of the N **newest**. Changed to `slice(0, N).reverse()` to correctly include the most recent logs and display them chronologically.

---

## [v2.1.2] — 2026-06-06

### Fixed
- **Episode guard regex**: Fixed `isDifferentEpisode()` not detecting episode changes when the MediaSession title uses `Sxx:Exx` format (colon separator, as used by Jellyfin/Emby). The regex character class `[\s\-\.]` was replaced with `[^a-zA-Z0-9]` to match **any** non-alphanumeric separator between season and episode numbers, preventing play/pause/seek commands from a different episode leaking through and incorrectly manipulating a peer's playback.
- **Per-device storage isolation**: Migrated `username`, `roomId`, `password`, `serverUrl`, and `useCustomServer` from `chrome.storage.sync` (synced across Google account) to `chrome.storage.local` (per-device). This prevents the extension from automatically joining the same room with the same name on multiple devices. Existing user data is migrated silently on first run; all preferences (`filterNoise`, `autoSyncNextEpisode`, etc.) remain synced.

### Changed
- Added one-time migration fallback in `getSettings()` and popup `init()` to copy existing user settings from `storage.sync` to `storage.local` on first launch after the update.

---

## [v2.1.0] — 2026-06-04

### Added
- Added full translation support for 7 new languages to both the browser extension popup settings and landing website: Italian (`it`), Polish (`pl`), Turkish (`tr`), Dutch (`nl`), Japanese (`ja`), Korean (`ko`), and European Portuguese (`pt`).
- Implemented robust, centralized browser system language detection mapping `pt-BR` to Brazilian Portuguese and other `pt` locales (like `pt-PT`) automatically to European Portuguese.
- Added flag emojis to language selector dropdowns in both the extension popup and landing/utility web pages for quicker visual identification.
- Added 181 translation keys parity validation suite checks for the new languages.

### Fixed & Hardened (Extension Audit)
- Guarded all website `localStorage` interactions to prevent initialization/join flow script failures on privacy-hardened or cookie-blocked browser configurations.
- Added robust validation null-guards to `chrome.runtime.onMessage` listeners across all extension scripts (`bridge.js`, `content.js`, `background.js`, `popup.js`) to reject unexpected runtime messages.
- Guarded CustomEvent payload destructuring in `bridge.js` to ensure stability when receiving third-party page events.
- Wrapped `video.currentTime` seeking adjustments during forced sync in content scripts with exception handling to absorb uninitialized video state DOMExceptions.
- Added payload validation guards on incoming Socket.IO events within the background script's event handlers to secure against malformed server updates.
- Prevented noisy browser console exceptions from context invalidation in target tabs by catching promise rejections on extension message dispatches.

### Performance
- Implemented in-memory language dictionary caching in the background script to completely avoid redundant extension package filesystem reads during translations.


---

## [v2.0.8] — 2026-06-03

### Fixed
- Fixed a bug where switching language inside the extension popup overwrote dynamic fields (such as active room ID, connection status, active server details, and video debug info) with default localized placeholder texts.
- Fixed a version reporting mismatch where the copied logs (debug reports) and connection handshake parameters incorrectly reported the hardcoded `1.9.0` version instead of the actual installed manifest version.

---

## [v2.0.7] — 2026-06-03

### Added
- Added a `DEBUG_LOGGING` environment variable to the relay server (defaulting to `"0"` / disabled) to prevent console spam from verbose connection (`CONN`), room activity (`ROOM`, `DEDUPE`), and `CORS` events under load. Critical logs like `SERVER`, `SECURITY`, `AUTH`, and `ERROR` remain enabled at all times.

---

## [v2.0.6] — 2026-06-03

### Performance & Security Hardening
- Optimized failed authentication attempts cache eviction algorithm to $O(1)$ by exploiting Javascript `Map` insertion-order properties. This completely removes the previous array copying and sorting bottleneck, neutralizing a potential main-thread blocking DoS vector under heavy brute-force password traffic.

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## [v2.0.5] — 2026-06-03

### Security & Hardening
- Hardened extension room idle auto-leave detection to correctly recognize when the target tab's video heartbeat goes stale (e.g., after tab navigation or media closure).
- Exported cleaner graceful shutdown and lifecycle methods (`stopServerForTests`) from the relay server to prevent socket leaks and port-binding conflicts during verify checks.

### Added
- Added a validation step in `test-locales.js` to ensure the supported language list in `extension/i18n.js` is perfectly synchronized with the actual JSON translation files in the locales directory.
- Added a robust route verification test suite (`scripts/test-server-routes.mjs`) covering rate limit throttling, caching headers, and admin metrics access control.

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## [v2.0.4] — 2026-06-03

### Security & Hardening
- Hardened relay health endpoints against simple flood traffic: `GET /` and `GET /health` are now limited to 10 requests per minute per client IP.
- Added lazy 60-second server-side caching for `GET /`, basic `/health`, and admin `/health` JSON responses to reduce repeated health-check work under noisy polling.
- Added stricter brute-force throttling for invalid admin metrics bearer attempts.
- Added startup warning for short `ADMIN_METRICS_TOKEN` values and documented that production Node ports must stay private behind Caddy or another trusted reverse proxy.
- Lowered the default maximum peers per room to 25.

### Added
- Optional privacy-preserving admin metrics on `/health` when `ADMIN_METRICS_TOKEN` is configured and a valid bearer token is supplied. Metrics are aggregate-only and exclude room IDs, peer IDs, usernames, IP addresses, media titles, passwords, and other user-level data.

### Changed
- Removed `bcryptjs`; temporary room passwords continue to use keyed SHA-256/HMAC hashing as documented.
- Public room discovery is now rate-limited server-side to one refresh every 10 seconds per socket, with the extension refresh button locked for 11 seconds.

### Fixed
- Improved Shadow DOM video detection so real embedded players are not hidden by smaller light-DOM preview or placeholder videos.
- Fixed join-button timeout cleanup after join status responses.

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## [v2.0.2] — 2026-06-02

### Fixed
- Peer identity spoofing in relay server: client-supplied `peerId` could be used to impersonate other peers in PEER_STATUS events. Server now always stamps `peerId` with the authenticated sender's identity.
- Amazon domain detection: replaced broad `includes('amazon.')` substring check with boundary-safe regex that correctly matches all Amazon storefronts (`amazon.com`, `amazon.de`, `amazon.co.uk`, etc.) while rejecting lookalike domains.

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## [v2.0.1] — 2026-06-01

### Fixed
- Video detection on Prime Video: `findVideo()` now scores all video elements by size, duration, and mute state instead of picking the first one. Fixes 0×0 placeholder being selected over the actual player.
- History entries in debug report showing `?` instead of action names.
- Prime Video status in compatibility matrix updated to reflect partial support.

### Added
- Multi-video overview table in Copy Debug Report when a page has more than one `<video>` element. Shows resolution, mute state, playback state, readyState, duration, and marks the currently targeted video.

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## [v2.0.0] — 2026-06-01

### 🌍 Multi-Language Extension (Biggest Feature!)
- **6-Language UI**: The browser extension is now fully translated into **English, German, French, Spanish, Portuguese (Brazilian), and Russian**. Switch languages instantly in Settings without reload.
- **Real-Time i18n**: Every label, button, tooltip, toast notification, empty state, and onboarding guide updates dynamically when the language changes.

### New Features
- **Copy Debug Report (Markdown)**: The *Copy Logs* button in the Status tab now copies a fully formatted Markdown debug report — system info, connection status, video diagnostics, action history, and logs. One click, paste into a GitHub issue, all debugging data ready.
- **Platform Auto-Detection**: The Dev tab now identifies streaming platforms (YouTube, Netflix, Twitch, Prime Video, Disney+, HBO Max, Vimeo, Dailymotion) and displays the detected platform.
- **Enhanced Video Debug Info**: 20+ new fields in the Status tab including network state, buffered ranges, dimensions (with 0×0 warning), media error codes, shadow DOM status, seeking/ended/loop flags, volume, playback speed, and data attributes.
- **No-Video Diagnostic Mode**: When no video is found, the Status tab shows platform, page title, video count, shadow DOM presence, and MediaSession data to help troubleshoot.

### Changed
- **New TwoPointZero Branding**: Updated extension icons (16/32/48/96/128px).
- **Larger Popup Logo**: Extension popup icon increased to 48px.
- **Prime Video Unblocked**: Removed `amazon.` from the tab blacklist so Amazon/Prime Video tabs appear in the video selector.
- **Improved Debug Report**: Full User-Agent string for accurate browser identification, UTC timestamp, connection details including server URL and room info.
- **Smart Disconnect**: Improved disconnect handling when leaving rooms.
- **Human-Readable Room IDs**: Expanded word lists for friendlier room names.
- **Custom Server Support**: WEB_JOIN_REQUEST and join button for custom server invite flows.
- **Reconnection Strategy**: Custom server reconnection improvements.
- **Episode-Aware Sync**: Command sequencing with smarter episode transition detection and echo suppression for smoother series binges.
- **Sync Status Refinements**: YouTube and Twitch sync behavior improved.
- **No External Dependencies**: Extension remains dependency-free with no library overhead.

### Fixed
- Hardcoded strings, missing translation keys, and Service Worker notification race conditions.

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## Versioning Policy

- **MAJOR** (x.0.0): Breaking protocol changes, architecture rewrites, or major feature milestones.
- **MINOR** (0.x.0): New features, significant enhancements, new translations, or UI redesigns.
- **PATCH** (0.0.x): Bug fixes, minor improvements, and documentation updates. PATCH releases may not receive individual changelog entries if bundled with a MINOR release.