Our client uses 9:16 videos for some of their product media (clothing store) through Vimeo. Shopify grabs the thumbnail in a 16:9 format. It grabs only a small section of the actual video and is super pixelated.
It seems to be fine for videos uploaded to the Shopify CDN though.
Ok, so I’m an idiot here lol. The Vimeo thumbnails are landscape when they’re a portrait video. I’d say that’s our problem. I didn’t even think to check that. Thanks!