Unfortunately Damus doesn’t know how to render images at a URL with no file extension. From that website you’d have to download it and then upload it to nostr.build to get it to look right.
Discussion
I'm going to have a play around with their API tomorrow and see if I can use it to get the image URL instead of the webpage one, here I was just using a generic widget they have on offer. Will also look in to what other free image upload services are available.
Cloudinary was a mistake, it's good but once you reach the limit on a free account the paid ones are too expensive.