FreeBSD in QEMU no longer able to switch from ttyv8 (e.g. SDDM) to vt at another tty

No response to normal keyboard or mouse input at ttyv8, so login to a desktop environment is impossible.

Using Virtual Machine Manager to key Ctrl+Alt+F2 (pictured below) does not switch to ttyv1.

Weird.

This machine did previously work.

Comparison

I'm reminded of a bug that sometimes prevents use of vt(4) in VirtualBox, however I doubt that the root causes are the same:

• FreeBSD-RELEASE in VirtualBox: vt no longer visible when switching away from a desktop environment at ttyv8 : r/freebsd