@snailerotica and I think I know why the 2nd image is rendered wrong, my theory is because of bad image down-scaling.

I can see the artifacts from a fast but bad resizing, where the algorithm just skips pixels to match the target size.

Seems to me the image has exactly the black lines on the spots where this algorithm would show a pixel/line. A proper one would do an average filter so each downscaled pixel takes into account surrounding pixels too.