This was in the hacker Zeitgeist a few years ago, when "Secret Dots from Printer Outed NSA Leaker", though it's unclear whether the dots were used or if it was

This was in the hacker Zeitgeist a few years ago, when "Secret Dots from Printer Outed NSA Leaker", though it's unclear whether the dots were used or if it was one of the other opsec failures. https://news.ycombinator.com/item?id=14494818 https://news.ycombinator.com/item?id=14494818