To reproduce:
1. Create a new project;
2. Enable VR (Edit > Project Settings > Player > XR Settings);
3. Set OpenVR as VR SDK;
4. Go to Other Settings, turn off "Auto Graphics for Windows" and set it to OpenGLCore;
5. Enter Play mode, move your headset around and press Steam VR menu button with your Vive Controller;
6. Exit Play mode and repeat 4-5 steps with Direct3D11.

Expected result: when opening the SteamVR dashboard, head tracking still works with OpenGLCore.
Actual result: head tracking is disabled when the SteamVR dashboard is pulled up when using OpenGLCore.

Reproduced on versions: 2017.2.1p3, 2017.3.1f1, 2018.1.0b6, 2019.1.0a11

Tested and reproduced with HTC Vive.