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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How about this: Don't fiddle around with custom thumbnails as those are made for reason. On top of this, how about always showing the custom thumbnail on a video and show preview thumbnail when cursor goes on top of video and custom thumbnail returns when cursor leaves. Profit.