Under the heading == Fixing broken keys ==, 2. Find broken scan codes:
please consider adding the magic key for getting out of
"sudo /usr/lib/udev/keymap -i input/eventX"
perhaps just the addition of one sentence that I found herein:
"You can stop the program using <Esc>, and <Ctrl>+C."
(Difficult to search on https://duckduckgo.com
when you have to copy/paste letters using the mouse. ;-)