- Load Base and React videos from Local or Link (YouTube/direct).
- Press S to sync, D to desync. Use FR to force re-sync.
- Use Space to play/pause the focused video.
- Seek with Arrow keys. Hold Shift to target the base video.
- Adjust delay with − / + buttons. Use , / . for frame-level (~33ms) adjust.
- Adjust speed with [ / ] and reset to 1.00x with \.
- For YouTube, use Q to change quality.
- Drag the React window using the left handle. Resize from the bottom-right corner.