When I play a YouTube video, something like this pop’s up (turning the speech of the video into text or “captions” as they seem to call it. (I wouldn’t call it captions, because captions should appear at the bottom of the video, not in a separate pop-up.)
From the best I can tell, I have turned it off on the “Accessibility” settings, yet it pops up again each time I open a new video on YouTube.