To bring this back to the behavior your looking for please SSH into your RPi and
sudo nano /etc/systemd/logind.conf
and change the line
#HandlePowerKey=poweroff
to instead read (make sure to remove the hash)
HandlePowerKey=ignore
and then ctrl-x, y, and then enter to save and exit. Now reload that with
sudo systemctl restart systemd-logind
Your power button should now only trigger the kodi menu.
@sam_nazarko should this be a change on our end? I can’t think of why we would ever want the OS grabbing the power button outside of Kodi like this.