Accessibility / Media / Caption Quality Heuristics Bookmarklet

The Caption Quality Heuristics bookmarklet analyzes caption track quality for videos. Finds all video elements, filters to caption/subtitle tracks, analyzes cues for reading speed (words per minute), gaps between captions (dead air where no captions appear), overlapping captions, and displays an alert with statistics for each track: track label, WPM rate, total gap time in seconds, and overlap count. High WPM (>180) may be too fast to read comfortably; gaps indicate missing content; overlaps indicate poor caption timing.

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