Graphics on loading screen are visibly spliced

The background image of a Minecraft world with multiple biomes has an error. Where the mountain in the center of the image slopes off on the right side, a splice line occurs. The strange thing is, the line does not span the image, but only the middle part. To see the problem, you may need to restart the launcher a few times, as the background disappears when the launcher finishes loading. The error is small, but it is there.