I am making a scrolling ui panel and apply mask to ScrollRect component, which should hides parts outside panel area. I am using unity version 5.4.2f2-GVR. Mask work correctly on pc when i deploy it on google pixel device its not working. Is this bug of unity version or something else....
I got around this issue by using RectMask2D Component instead of the regular Mask.
If somebody else got this problem and Bahman_Aries solution is not enough, try this:
File > Build Settings > Player Settings>XR Settings (or Other settings if you are working in older versions of unity) > Daydream (click on the small arrow) > Depth Format.
And set that to 24-bit depth | 8-bit stencil.
This is cause you need a stencil buffer.
ScrollRect component has this weird behaviour when an image in its content has its material set to something other than none.
Unset the material to None and it should work.
If every child of content already has no material, then it could be a bug.
来源：https://stackoverflow.com/questions/41426351/unity-ui-mask-not-working-on-google-pixel-device