Hello there,
I guess there is no official documentation on this as there are several forums on this topic.
WSL uses the 9P protocol to share files between Windows and WSL. However, this process only appears starting in WSL 0.70.4. Although there is nothing mentioned about it in the 0.70.4 release notes, the 0.70.5 notes mention fixing a race condition in (what is likely) this component.
Hope this resolves your Query !!
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