Karabiner-Elements: Unable to load kext on High Sierra (10.13)

Obviously High Sierra is still very early, at Developer Preview 1, but I thought I’d mention that the Karabiner Elements 0.91.1 kext is not able to be loaded:

kiryo:~ root# kextutil -v 6 /Library/Extensions/org.pqrs.driver.Karabiner.VirtualHIDDevice.kext/
Kext user-space log filter changed from 0xff2 to 0xfff.
Kext kernel-space log filter changed from 0xff2 to 0xfff.
Kext library architecture set to x86_64.
Can't stat /AppleInternal - No such file or directory.
Defaulting to kernel file '/System/Library/Kernels/kernel'
Kext library recording diagnostics for: validation authentication dependencies warnings.
/Library/Extensions/org.pqrs.driver.Karabiner.VirtualHIDDevice.kext appears to be loadable (not including linkage for on-disk libraries).
System policy prevents loading the kernel extension.
kiryo:~ root# 

I verified it with codesign and it appears to be fine:

kiryo:~ root# codesign --display --verbose=4 /Library/Extensions/org.pqrs.driver.Karabiner.VirtualHIDDevice.kext/
Executable=/Library/Extensions/org.pqrs.driver.Karabiner.VirtualHIDDevice.kext/Contents/MacOS/VirtualHIDDevice
Identifier=org.pqrs.driver.Karabiner.VirtualHIDDevice.v040600
Format=bundle with Mach-O thin (x86_64)
CodeDirectory v=20200 size=1138 flags=0x0(none) hashes=29+3 location=embedded
Hash type=sha256 size=32
CandidateCDHash sha1=9dab0ba54dd0ec03c72e50593e69fb75819336a7
CandidateCDHash sha256=91f95ed243acbf16c435025dd467091d428ce6b0
Hash choices=sha1,sha256
Page size=4096
CDHash=91f95ed243acbf16c435025dd467091d428ce6b0
Signature size=8959
Authority=Developer ID Application: Fumihiko Takayama (G43BCU2T37)
Authority=Developer ID Certification Authority
Authority=Apple Root CA
Timestamp=25 May 2017 at 17:45:47
Info.plist entries=20
TeamIdentifier=G43BCU2T37
Sealed Resources version=2 rules=12 files=0
Internal requirements count=1 size=212
kiryo:~ root# codesign --verify --verbose=4 /Library/Extensions/org.pqrs.driver.Karabiner.VirtualHIDDevice.kext/
/Library/Extensions/org.pqrs.driver.Karabiner.VirtualHIDDevice.kext/: valid on disk
/Library/Extensions/org.pqrs.driver.Karabiner.VirtualHIDDevice.kext/: satisfies its Designated Requirement
kiryo:~ root#

This install was upgraded from Sierra, where I was using the fork of 0.90.68 with Hyper key support, and that continued to work after the upgrade, and my Gatekeeper settings are still to allow App Store & Identified Developers.

I think the errors involved here are new, at least I haven’t seen them anywhere else, and Google doesn’t seem to know about them, so maybe some kind of kext policy has changed in 10.13 - except I would note that Little Snitch’s kext loads fine.