Reasons for "Failed to initialize WebGL."

[zhangyiatmicrosoft]

We have an app using the control and received reports from end users complaining errors "Failed to initialize WebGL.". By adding detailed debug (like this one #1715) two most common errors are:

Could not create a WebGL context, VENDOR = 0xffff, DEVICE = 0xffff, Sandboxed = no, Optimus = no, AMD switchable = no, Reset notification strategy = 0x0000, ErrorMessage = OffscreenContext Creation failed, GpuChannelHost creation failed.

Web page caused context loss and was blocked

The error happens during map creation and the above messages do not help much. Anyone has more insights regarding why and how to fix? Much appreciated!!!