subtitle.im is a desktop Chrome extension that manages existing YouTube captions. Modes are Follow YouTube, Auto-open and Auto-close. OCR running in the browser detects burned-in subtitles, and video frames are not uploaded. Duplicate soft captions can be closed automatically, closed after asking, or kept. Detection can miss subtitles or give false positives.
Free is $0, with no sign-up needed, and includes 10 successfully handled videos in total with no monthly reset. Pro is $17.99 per year, billed annually and renewing each year, and Pro Lifetime is $29.99 once. Pro adds unlimited videos, channel rules, video rules and remembered closures.
Burned-in subtitles and YouTube soft captions can overlap. The aim is to give viewers control over existing captions and use local duplicate detection to help avoid two subtitle layers.