REPRO STEPS
1. Build/deploy attached project for UWP, x64, local machine
2. run the app
3. Press Q to enable VR mode
4. Focus the HMD (Win+Y) and press E to disable VR mode
5. Repeat 3-4

> UnityPlayer.dll!win::ComPtr<UnityWinRTBase::Windows::Graphics::Holographic::IHolographicSpace>::operator->() Line 87 C++
UnityPlayer.dll!VRDeviceHoloLens::BeginRenderingToDeviceGfxThread() Line 628 C++
UnityPlayer.dll!HoloLensEventGfxThreadCallback(UnityVREventGfxThreadType eventType, unsigned int data, const UnityVRGraphicsContext * graphicsContext) Line 370 C++
UnityPlayer.dll!VRDevice::SendVRDeviceEvent(unsigned int eventID, unsigned int data) Line 1611 C++
UnityPlayer.dll!GfxDevice::SendVRDeviceEvent(unsigned int eventID, unsigned int data) Line 1718 C++
UnityPlayer.dll!GfxDeviceWorker::RunCommand(ThreadedStreamBuffer & stream) Line 2330 C++
UnityPlayer.dll!GfxDeviceWorker::RunExt(ThreadedStreamBuffer & stream) Line 490 C++
UnityPlayer.dll!GfxDeviceWorker::Run() Line 476 C++
UnityPlayer.dll!GfxDeviceWorker::RunGfxDeviceWorker(void * data) Line 454 C++
UnityPlayer.dll!Thread::RunThreadWrapper(void * ptr) Line 78 C++
kernel32.dll!BaseThreadInitThunk() Unknown
ntdll.dll!RtlUserThreadStart() Unknown