Ok so I’ve done the retro reviews for BeOS and Alpha 1 and these builds feature this box but afaik this hasn’t appeared in any builds since — today, I was shutting down my MacBook today and this appeared!
And no, this isn’t a mock-up or anything like that — it’s a straight pic taken from my phone of the screen 
Is the safe shutdown box making a comeback? 
Interesting! Apparently that has been in the Haiku codebase for quite some time. I think the reason you’re seeing it, is that usually ACPI would tell your computer to turn off itself, but that must have failed for some reason…
Yes, this is still there and appears only if we don’t manage to turn off the computer automatically using ACPI or APM. I think you can get it if you disable both of these in the boot menu?
I think Alpha1 had only APM and no ACPI? It’s been too long since then, so I’m not sure about that.
unfortunately, it is still there.
But sometimes if the PC does not shutdown, I wished it would be there.