This option is available only in the VR developer settings .
To access the option:
- Open a VR app, such as a Daydream app for Pixel XL
Go to the settings menu either through the regular menu (for example, in the Daydream application), or by clicking on the small gear in the upper right corner, if you are in stereo mode 
At the bottom of the list you will see the settings menu with the words "Build Version": tap it several times to activate the developer mode
- When developer mode is activated, you should find in it the option “Enable loading of the GVR SDK library”.
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