Can you get copyright from a thumbnail?

[Shakycow]

actually it wasn't The supreme court also mentioned that thumbnails in news reports/ blogs etc were all fair use

I hadn't read that in any of the cases I've seen (each strictly had to do with thumbnails on search engines), but news reports and blogs would be covered anyway- just as it's considered fair use to show clips of a movie when doing a news report.

Either way, a YouTube channel stealing and using another channel's thumbnails still wouldn't be covered under fair use.