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Does Docker download the image when using Windows Server Containers

I have installed Windows Server 2016 version14393.693, In dockerfile when I use
FROM microsoft/windowsservercore:10.0.14393.693
It starts downloading the image. According to the definition of Windows Server Containers, it uses the kernel of the host OS, so in this case why it is downloading the image whereas the host OS is same. It should use the host OS.

While the kernel is shared between between host and containers, the rest of the operating system userland is not. Imagine, for example, that you had changed dlls, removed or added dlls on the container host, and then tried to run a container built on an un-modified system (or built on a system with different changes). The results would be unpredictable, and you’d loose a major advantage of containers: That they run and work the same no matter where you run them.