Getting an error on that page in Chrome.
Refused to execute script from 'https://rawgithub.com/dmauro/Keypress/master/keypress.js' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled.
EDIT: It's because Keypress is using rawgit.com instead of cdn.rawgit.com to host the actual keypress.js script.Details here - http://rawgit.com/dmauro/Keypress/master/keypress.js
Working script source - http://cdn.rawgit.com/dmauro/Keypress/master/keypress.js