The author stumbled upon a video of a 9-year-old girl on a German TV show who quickly identifies differences between two similar images, which baffled the author. By crossing their eyes and overlapping the images, a third image is created where the differences stand out. The author felt like they gained a special superpower and shared the technique for others to try with easy, hard, and superhuman spot-the-difference puzzles provided. A link to a thread on Hacker News discussing the technique and sharing stories was also included.
https://danielwirtz.com/blog/spot-the-difference-superpower