Using Unity 2018.1.0f2 and Oculus Utilities 1.25.2
When I build to my S8 on Gear VR, the back button works as should by bringing me to the Oculus quit menu, as well as when I remove the headset it immediately pauses the app.
On my Oculus Go, I do the exact same build and neither of those things work. Am I missing something so that OVRManager.cs and OVRPlatformMenu.cs work on Oculus Go too?
I realized that the old Oculus dll where still in the project and weren't being overwritten by 1.25.2. So just deleted all OVR assets without Unity open and then installed OVR Unity integration from scratch. Works now!