In my case, I kind of worked backwards from the way eieio found it. I was at the very bottom of the million checkboxes when I noticed there was a repeating pattern. And if you zoomed out enough, and sized your window large enough, it looked like this: https://matrix.theblob.org/omcb-repeating-pattern.png
It was obviously a bot, but it definitely wasn't random. It was a pattern that repeated every 208 checkboxes. At first I thought it was a barcode, but it wouldn't scan even when I turned it into a form that should scan. Then, I figured it could potentially be a binary code, so I tried treating the repeating pattern as binary, with the checked boxes as 1s and the unchecked boxes as 0s. That got me the URL that eieio talks about in the original article.
Once I was there, I discovered from the other members that I had taken a more arduous route than I needed to; it turns out that the site's API was such that it sent its initial state as a base64-encoded version of the full binary state of the board. Decoding the base64 and looking at the end of the data would also have gotten you the same URL, and as such many of the people in the server were bot developers who had done exactly that because they wanted to reverse-engineer it.
