Hello @TeamYouTube , I would like to know, why are not the thumbnails of the videos on my channel? What happens is that all my videos had thumbnails, and now they are no longer seen.pic.twitter.com/10DKNkIopT
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I was at first alarmed by this, but based on their experiments with GIF hover thumbnails, I think they're trying to combat clickbait and misleading thumbnails. Or perhaps an alternate way to preview content to users with an actual frame from the video. We'll see how it turns out.