Hitting record used to capture from wherever the reel stood — at the end, the auto-stop fired a beat later and saved one second of the final frame. Recording now rewinds to the top and rolls the whole reel. And the container asks for MP4 (H.264) first, the format every phone and platform plays, keeping WebM only where the browser cannot mux it; the extension follows the container. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>