Does not Boot after upgrade to 2.50

[desperate250]

My pfsense VM does not Boot after upgrade to 2.50. It is a Proxmox VM.
The error message is ERROR: cannot open /boot/lua/loader.lua: no such file or directory

However, when I open the VM console and enter

boot (and press Enter)

the system boots normally. What can I do to get automatic boot again?

I have restored a backup to a new VM, so I have a running system. So this is not urgent.

[crimper]

That happened to me as well on Proxmox. The upgrade went smoothly and rebooted without incident the second time around.

[desperate250]

I tried it again with a copy of the original VM. Still the same error. Seems to be an incompatibility issue with Proxmox or their Bios.