Autostart JMRI PanelPro on a Raspberry Pi -- without launching two instances.

autostart

# Full path: /home/pi/.config/lxsession/LXDE-pi/autostart
@lxpanel --profile LXDE-pi
@pcmanfm --desktop --profile LXDE-pi
@xset s off
@xset -dpms
@xset s noblank
@/home/pi/jmri-runner.sh

jmri-runner.sh

#!/bin/bash
# Full path: /home/pi/jmri-runner.sh

# Sleep to hopefully wait until the window manager is fully started.
# Added because I would sometimes start up the RPi and find that PanelPro was running,
# but not visible in the window manager. Maybe there is a better way?
sleep 10

lock=/tmp/jmri-runner.lock

flock --nonblock $lock ~/JMRI/PanelPro
if [ $? -ne 0 ]; then
    echo "PanelPro is already running. $lock is locked."
    exit 1
fi

Does not seem to run on my setup (Rpi4B with Buster, updated and upgraded), Java 11.0.16, headless with TightVNC

1. lxsession is not present in my .config, instead there is /home/pi/.config/lxpanel/LXDE-pi, where I copied the autostart file
2. JMRI sits in /home/pi/Documents/JMRI
3. I adjusted the JMRI location in line 11 of autostart

Please help?

EDIT: according to https://forums.raspberrypi.com/viewtopic.php?t=294014 the autostart feature (system) for Buster resides in /etc/xdg/lxsession/LXDE-pi/ but when editing the autostart file already present there with the commands shown here, there still is no autostart of PanelPro

EDIT 2: and when creating the /home/pi/.config/lxsession folder and associated files, with the updated autostart file, still no PanelPro autostart.

EDIT 3: jmri-runner.sh must be made executable. When done now PanelPro autostarts.
I think issue is solved.

Even with 20 seconds delay the program (PanelPro) does not show up on the desktop even though the Taskmanager shows it running.
What to do?

EDIT: I have TightVNC server running from startup. Could that be the reason for not showing on a hdmi-connected monitor?