openbox-autostart

xset -dpms            # turn off display power management system
xset s noblank        # turn off screen blanking
xset s off            # turn off screen saver
Next if Chromium crashed it may pop up error messages next time it starts. This is another feature that we don't want in a kiosk.

# Remove exit errors from the config files that could trigger a warning

sed -i 's/"exited_cleanly":false/"exited_cleanly":true/' ~/.config/chromium/'Local State'

sed -i 's/"exited_cleanly":false/"exited_cleanly":true/; s/"exit_type":"[^"]\+"/"exit_type":"Normal"/' ~/.config/chromium/Default/Preferences
Finally, update autostart to run the Chromium browser in kiosk mode. Pass in an environment variable ($KIOSK_URL) that contains the URL of the Web app to launch.

# Run Chromium in kiosk mode
chromium-browser  --noerrdialogs --disable-infobars --kiosk $KIOSK_URL