The way to autostart
using .config/lxsession/LXDE-pi/autostart
is no longer available on the lastest RaspberryPiOS(bookworm).
Instead the following way is available.
mkdir -p .config/autostart
nano .config/autostart/chromium.desktop
The content of the file is like:
[Desktop Entry]
Type=Application
Exec=chromium-browser --kiosk --incognito https://lmlab.net
Tip: Alt + F4
to terminate the process.
See the following page for more details(very excellent document!):