http://lxqyom6a3p6fdgsy6mpjyhjqjdpzleseck2jojwwzcilmsvduaeo7zyd.onion/2020/06/22/three-ways-to-hack-bitcoin/index.html
At the time, all Dropbox accounts came with a public folder, so that everything you put there was exposed to the web, and much of it was picked up and indexed by Google. People were sloppy (or just plain stupid?), and more than one person decided this folder was the perfect place to store a backup of their Bitcoin wallet in.