Proxmox-local-gui

Install xorg, Chromium and Openbox

From a proxmox terminal as root:

apt update

apt install --no-install-recommends -y xorg  chromium openbox

Add new local user (pam) with minimum privalages to launch chromium with xinit

useradd kiosk
passwd kiosk
mkhomedir_helper kiosk

Openbox Configuration

Edit openbox autostart

nano /etc/xdg/openbox/autostart

replace with:

# Disable any form of screen saver / screen blanking / power management
#xset s off
#xset s noblank
#xset -dpms

# Allow quitting the X server with CTRL-ATL-Backspace
setxkbmap -option terminate:ctrl_alt_bksp

# Start Chromium in kiosk mode
#sed -i 's/"exited_cleanly":false/"exited_cleanly":true/' ~/.config/chr>
#sed -i 's/"exited_cleanly":false/"exited_cleanly":true/; s/"exit_type">
chromium https://127.0.0.1:8006 --kiosk --window-size=1920,1080 --incognito --noerrdialogs --disable-translate --no-first-run --fast --fast-start --disable-infobars --disable-features=TranslateUI --disk-cache-dir=/dev/null --password-store=basic

Edit .bashrc

append to the end of user "kiosk" .bashrc file

nano /home/kiosk/.bashrc

# start x openbox on login  see  /etc/xdg/openbox/autostart
[[ -z $DISPLAY && $XDG_VTNR -eq 1 ]] && startx

Optional. set login hint to MOTT

nano /usr/bin/pvebanner

After https://${localip}:8006/ add a message like:

Or login as user: kiosk  for local GUI access

Use ctrl + Alt + Backspace to exit GUI

References:

https://die-antwort.eu/techblog/2017-12-setup-raspberry-pi-for-kiosk-mode/