Steganography and hiding images in highlighted text.
Via Boing Boing, this fascinating new method of steganography, or the practice of concealing a message in plain sight:
Hiding images in highlighted text pic.twitter.com/Za0THkKBTn— Neal Agarwal (@nealagarwal) October 6, 2019
Related: From a couple of years ago, here's an interesting article at WIRED on the history and (somewhat terrifying) future of steganography.
At least we’ve moved beyond the approach to steganography that ancient Greek leader Histiaeus used in 440 BCE: shaving a trusted slave’s head, tattooing a secret message on his scalp, letting his hair grow in, and then sending him off to be shaved again by the message’s recipient. Or maybe those were the real glory days.