Created attachment 200838 [details]
Output of init(8) is suppressed in UEFI mode. There are only kernel messages on ttyv0.
Here is screenshot of clean 12.0-RELEASE booted in UEFI mode.
Created attachment 200839 [details]
One more screenshot shows the same instance booted in BIOS mode.
The problem occurs when FreeBSD started as guest OS under QEMU. CentOS 7 with qemu-kvm-ev-2.10.0-21.el7_5.7.1.x86_64 is used as hypervisor. UEFI firmware - edk2.git-ovmf-x64-0-20181129.805.g9601046bf4.noarch.
11.2-RELEASE works fine in the same conditions.
Also, 12.0-RELEASE works fine with ESXi in UEFI mode.