Yes @mojsiuk, I tried. It works. Please also check these URLs to fix the UEFI boot problem:
Dear Proxmox Team,
Thank you so much for PBS. It's a game changer product for PVE.
I'm trying to install Proxmox Backup Server on FreeNAS 11.3U3-2 as bhyve VM since it's recommended to separate installation of PBS from PVE.
Installing PBS on FreeNAS can save from using a separate physical...