I added the error tag. If you click the full size image, it shows an transparent_background where the artist must have accidentally erased the solid white background.
The background is pretty much completely white, except for a few small spots. I don’t think that qualifies as transparent background. Shouldn’t the background be completely or at least mostly transparent to qualify? That’s what I’d expect when searching for transparent background.
There’s actually several more images with such spots, intentional or not. I’ve been thinking about a sensible tag for that, like spot_transparency, but never got around to suggest it on the forum.
