https://i.artdude.uk/darkosto/uzuGlwu0.png

I'm still not quite sure why there are two images? Why does the default home image not follow this same structure? It should be simple to add a home image, not require me to spend hours on a non-essential part of a modpack.

I figured out while working on mine, that It's actually a messed up wrap of the same picture. To work around it, I had to create a PNG with top half of the canvas the picture, and the bottom half a blank background. So when the bottom half wrapped back over, it could not be seen.
Click below to see how blank background extends.