Does the Rift handle Screen Overlays differently than the Go?

I had a screen overlay applied when the character moves, to reduce vection.  I'm porting the app over from Go to Rift, and this effect seems to have gone away.  It could be a mistake on my part with the script, or wiring it up in Unity.  I am wondering though: Does the Rift hardware treat textures and overlays similarly to the Go?  The effect is basically a texture mask in an overlay that is applied when moving, and then removed when stopped.  Any pointers or info would be appreciated! 

got referred here, they work slightly differently on Rift-
https://developer.oculus.com/documentation/unity/latest/concepts/unity-ovroverlay/