No? The quiz is clearly some kind of edge detection filter. The light blue "grid" is the background to let you know there are transparent pixels in the expected output. It looks like something designed with intention to me. They just forgot to put the text description.
Never mind, you were right that it is edge detection (a terrible one though lol):
https://shaderacademy.com/shaders/glsl/ranked_1/fragmentExpe...
But I still stand by the ai-gen'd aspect
Hey, so I responded about it in other thread, but let me respond here.
Most challenges were created by us, but we use LLM for example to generate comments in the code or generate some simple boiler plate.
Sometimes, it is also useful to create similar challenge to already existing one.
Click on where it says DIFF; its not edge detection
More likely to be some kind of color space thresholding