ReadonlywaitReadonlyffmpegReadonlyvideoReadonlycolorReadonlystartWhere the capture began — the URL the recording context navigates to before prepare replays the script.
Deliberately supplied by the caller rather than read off the page being captured: by the time video runs, a scripted state has already driven that page, so its current URL is where the script ended. Replaying the script from there records the wrong thing — a step that navigates would run from the wrong entry point, and a first step that assumes the entry view fails outright.
Optional ReadonlyprepareReplays a scripted state inside the recording context.
Without it the video context would navigate and record the unscripted boot view while the stills show the scripted state — the two silently disagreeing. Undefined for route captures, so existing behaviour is untouched.
Must match the screenshot context, or a run's stills and video disagree.