Using EmbedBuilder WithThumbnailUrl limits

[mwpowellhtx]

Are there any limits with EmbedBuilder.WithThumbnailUrl... I am trying to attach an image, literally this, but it seems as though discord is taking some liberties, perhaps cropping the image:

However this is being posted,

A similar approach, I can say the approach is the same, in another aspect of the same algorithm, the result is what I expect:

The only thing I can think of is that perhaps the troubled image is 1024 x 1025, not 1024 x 1024, as the target subsequent examples are.

[mwpowellhtx]

Ah never mind... Snafu on my part, the channel send was involving a different image path altogether. So that posted, without the image and thumbnail embeds.