LagSync Releases

Privacy

• Feature: Added a "Turn off and pause usage stats" toggle in Settings → Privacy. Default is on. Stats are stored locally on this device only — they are never sent anywhere.
• Feature: Turning the toggle off opens a confirmation prompt with three choices: Cancel, Pause only (keep existing stats), or Pause & delete (clear all stored stats).
• Improvement: While paused, the Stats page hides all content and shows a "Usage stats are paused" message with a "Resume usage stats" shortcut. The background heartbeat skips recording entirely while paused, so nothing accumulates.

Edge support

• Fix: Delay now applies on all sites in Microsoft Edge. Some Edge builds don't reliably run manifest world: "MAIN" content scripts at document_start, silently leaving the MSE/WebAudio/canvas hooks uninstalled. page_script.js is now also injected from the content script (with a double-init guard) so the hooks install on every Edge build.
• Fix: Twitch (and other blob-backed live streams) now uses the frame-capture canvas pipeline on Edge, matching Firefox. The worker-MSE timestamp-offset path that works on Chrome did not produce a visible delay on Edge for these streams.

Sync engine and stability

• Fix: Prime Video Instant mode now applies as a single hard jump instead of burst steps. Prime's player was rebuffering on the ramped bursts; a single jump avoids the stall while still being instant.
• Fix: Twitch startup regression when LagSync is already enabled at page load. Worker/live-edge config is now refreshed automatically on startup, so delay applies without requiring a manual toggle.
• Fix: Reduced startup stutter on Twitch/Edge by avoiding unnecessary WebAudio hooking in positive-delay mode.
• Improvement: Instant increase mode uses safer near-instant burst behavior in no-trim contexts to reduce boundary-time stalls/rebuffering (except on Prime, see above).
• Improvement: YouTube Instant mode uses near-instant burst stepping for faster feel with better stability.
• Fix: YouTube live streams that disable seeking backward (no-DVR live) now apply delay correctly via the canvas frame-capture pipeline, since MSE timestampOffset shifts would rebuffer against the pinned live edge.

Timing and controls

• Fix: Toggling LagSync off now shows 0 ms immediately in the popup. Previously the popup kept displaying the last-applied delay (e.g. 180 ms) until it was closed and reopened, and as a side effect the next toggle-on skipped its countdown.
• Fix: "Starts adjusting" countdown estimation is more accurate on YouTube/VOD by limiting seekable fallback to trim-blocked contexts.
• Fix: Speed and max-buffer settings now apply immediately on first click (no stale value delay).

Docs

• Added: Browser differences doc covering the per-browser pipeline choices (Chrome MSE vs Edge/Firefox canvas on Twitch, Firefox/Safari/Edge injection path, etc.).
• Added: Detailed timing/mode behavior documentation, including the Prime Video Instant exception.
• Added: Technique and site-type behavior map (DRM/live-edge/worker/blob/iframe/etc.).

• Fix: keep Twitch/HUD visible by inserting delayed canvas sibling with z-index 0.
• Feature: capability-based pipeline selection (MSE vs canvas) instead of host hardcoding.
• Fix: Firefox Kick compatibility with srcObject detection and rAF + createImageBitmap fallback.
• Fix: stabilize canvas pipeline to avoid black flashes and ensure setting changes apply reliably.
• Improvement: generalized "twitch" naming to a generic canvas/live-edge pipeline.
• Major Update: refactored codebase to TypeScript for stronger type-safety and reliability.
• Feature: added compatibility for Prime Video.

• Initial release.
• Core lag sync features via MSE.
• Bluetooth audio delay compensation.
• Basic audio/video offset controls.