The KeyboardEvent |code| attribute contains information about the key event that can use used identify the physical key being pressed by the user.
Docs: https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/code
Samples: https://googlechrome.github.io/samples/keyboardevent-code-attribute/ https://w3c.github.io/uievents/tools/key-event-viewer.html