Vulkan error in vrclient_<app name>_log.txt

[phr00t]

This error happens in the vr client log for the built Xenko applications:

Sat Mar 09 2019 16:52:07.012 - IVRSystem::GetOutputDevice: Failed to get required Vulkan device function pointer (vkGetPhysicalDeviceProperties2KHR)!

... however, I haven't noticed any symptoms in the application... not sure if this is a big deal or not. I have a thread open with SteamVR support to check on this. I'm not worried about it at the moment, though.