my version
### Start Ventoy Multiboot
GetHotkey
menuentry "Ventoy Multiboot" --hotkey=${hotkey} {
if [ -n "$pc" ]; then
GetDiskPartNum
chainloader (hd${disknum})+1
elif [ -n "$efi" ] -a [ -e /EFI/BOOT/BOOT${_SPEC_UEFI_ARCH}.efi ]; then
GetDiskPartNum
set root=(hd${disknum},msdos2);
chainloader /EFI/BOOT/Boot${_SPEC_UEFI_ARCH}.efi;
fi
}
### End Ventoy Multiboot