You should be able to upload to snaps. Any reason they couldn't @asgarth ?
As for the answer to the question... hat particular model doesn't allow us to choose a file type and they default to this new image type .webp
Ideogram does the same but they at least do .png
That was indicated in the FAQ section of the article but happy to explain it here as well.
My files on my computer wasn't set to show all files.
So the error was in my brain and nothing to do with peakd :D