This is the same general method as I used to quickly solve "spot-the-difference" games as a child. Just cross your eyes until the images match and let your brain pick out the disparities.
Does this method also work when I'm missing a semicolon somewhere between lines 35 and 994?
Use an IDE or a linter.
Or git diff
I had never thought of that... amazing how easily the eyes track the overlapped image if you move your head forward and backwards.. I have to stay exactly on the plane splitting the two images or else the illusion breaks immediately.
I thought this was a joke, it takes a moment to get the focus right but suddenly all of the differences appear. Thanks for sharing your childhood hack!
That is totally awesome. Once you get the focus right, the changes just light up.