I recently signed up for the PlayCanvas newsletter and I got an email in which they linked a deprecated WebVR project.
The project’s dev log feed links to github, which states that the project is outdated and says:
This project is now deprecated. WebVR support for PlayCanvas is now built directly into the engine. For more information see the developer documentation: http://developer.playcanvas.com/en/user-manual/vr/
But the developer documentation link leads to an empty page.