Your browser doesn’t support VP8 encoding via WebCodecs, which this tool needs for bitstream-level moshing. Try a Chromium-based browser (Chrome, Edge, Arc, Brave…) or a recent Firefox.
After one initial keyframe the encoder is never allowed another, so the picture accumulates drift and smear on its own. Hold Bloom to re-apply the last P-frame’s motion over and over; hold Drop to discard frames so reality jumps when you release; Resync lets a single keyframe through to snap back to clean video.
Drop a video or start the webcam.