Add a trailer beat or a text card at a seam.

A new text card: its words, and its style (absent: a statement). It runs as long as the words take to read, 2.5–6 s. A text beat is words plus a style: statement (A theme or a title: one idea, centred, each word rising in out of a soft blur. At most 7 words.); thought (An interior line, a question or a note to self, low on the left, each line rising in. At most 14 words.); typed (Words being typed (a prompt, a search, a line the character writes), letter by letter with a blinking caret. At most 12 words.); reveal (An editorial title or a chapter name: a thin rule draws, then the line wipes on. At most 6 words.); label (Names what the product just did, beside the screen: small capitals on a dark pill. The only style a screen recording carries. At most 4 words.); stat (A number that matters ("3 hours back"): the number counts up, its words rise under it. At most 4 words.); directed (Anything else, moved the way plain words describe it (through the motion direction). At most 20 words.). Absent, a text card is a statement, words over picture a thought, and a screen recording's words a label. Tempo calm, standard or brisk; place centre, lower, upper, left or right; enterOn cut, a narrator word, or the score's downbeat; emphasis marks up to 2 exact words. A text change is free; a rendered cut is rebuilt free.

How the beat's words will play once drawn by the master, and the cut's text density rules it breaks.

On a rendered trailer with no screenplay, a blank beat holds its video: nothing rebuilds it until each blank beat is a capture beat or a title card, or removed (then it is rebuilt, free); the answer's masterHold names the beats and the fix, and the export is refused with it (trailer_capture_only).