Chrome Version: 69.0.3497.100 (Official Build) (32-bit)
OS: Android

What steps will reproduce the problem?
(1) Navigate to one of the top results of a search for "webvr demos", like https://experiments.withgoogle.com/collection/webvr or https://webvr.info/samples/
(2) Play one of the demos, i.e. https://webvr.info/samples/03-vr-presentation.html

What is the expected result?

Expect demo to take over the full VR experience.

What happens instead?

Instead it seems to enter full-screen presentation mode and in some cases render the binocular rendering into Chrome's WebVR environment.

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If this is a regression (i.e., worked before), please consider using the
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For graphics-related bugs, please copy/paste the contents of the about:gpu
page at the end of this report.