Toshiba Satellite C850 OS 12.1 86x64 reboots after shutdown when connected to AC Power. Shuts down OK on AC Power with Windoze. Shuts down OK with battery only.

With AC power connected, the command 'shutdown -P' and GUI menue "shutdown" results in the laptop doing a hard reboot.

Applies to OS 11.4, 12.1 and 12.2.