That should go away after a second or two, when the page finally responds to the resize/orientation change. Why resize/orientation change is so slow is a question for blink people.

If the white strip never goes away, that's a new bug but I'm not seeing that.

I attach a screen shot, marked it with RED. Not sure if this is the white strip you referred. It will not go away.  And this also exist for treasurehunt(NDK/GvrLayout).

But when add gvrLayout.getUiLayout().setEnabled(false), this vertical white strip go away.

Deleted: VR_ShiteStrip.png 2.0 MB

	VR_ShiteStrip.png 2.0 MB View Download

This is the divider that indicate the alignment of left and right eye rendering. It is part of the Daydream UI(similar to close and gear buttons). And all Daydream VR app should have the same thing. In daydream headset, you should not be able to see it. 

I am afraid bshe@ is talking about the horizontal white strip as whitestrip650366.png depcited. Also I attach a video for this.

Deleted: whitestrip650366.mp4 4.6 MB

	whitestrip650366.mp4 4.6 MB View Download

Deleted: whitestrip650366.png 20.8 KB

	whitestrip650366.png 20.8 KB View Download

As I mentioned earlier, that transient white strip is an artifact of the page resizing asynchronously. In the case of webVR, this transient state may go away with renderer improvements in the future, but right now it's expected behavior that isn't fixable.