[Feature request] Allow initgfx to work on read-only root filesystems

[probonopd]

In helloSystem, we would like to have a system that can be booted from truly read-only media such as DVD-ROM.

Setting Up FreeBSD for Read-Only Booting makes it seem like it is possible to boot FreeBSD from read-only media. Looks rather simple! Exactly what we would like to use.

But then, initgfx currently assumes it can write in many places.
Currently helloSystem needs a giant workaround that copies the whole system into RAM, just to make initgfx work. We also tried to use unionfs but could not get it to work with initfgx.

So the question is:
Would it be possible to change initgfx in a way so that it only writes in /var/run?
One could symlink the files/directories it needs to write to /var/run.

After all, I think that conceptually any data that initgfx touches is transient in nature, it is auto-generated on the fly and cached, but should not be persisted. So, exactly what /var/run is for?