- Open the video on youtube.com
- Pause the video and use , / . to fine-tune the frame
- Right-click → Copy debug info
- Paste it below
- Paste the Twitch VOD URL and (optionally) an approximate start/end time below
- Click Queue download — you can queue several at once
- Once a download shows "Ready," click Load
- Use the ◀/▶ buttons or , / . to step frame by frame
- Click Mark start and Mark end to log the time