systemd-units/x11vnc@.service~

[Unit]
Description = x11vnc startup
After=wm.target

[Service]
ExecStart = /usr/bin/x11vnc -ncache_cr -ncache 10 -passwd 3392idst -forever
Environment=DISPLAY=%i # <= !
Restart = always

[Install]
WantedBy = mystuff.target