Printing press, depending on your view of taming.

There’s a 1520 encyclical related to the matter: https://www.papalencyclicals.net/leo10/l10exdom.htm

Joseph's 404 article quotes the hacker as saying they "got admin privileges on a silver platter," so I think this is it: first part of the breach was gaining the GitHub permission to create a branch. Possibly just by asking.