It looks like alternize was almost right, at 4:39 you can see that within the Ubuntu (not /mnt) part, default permissions are used. e.g.: `ls -l proc` reveals t

It looks like alternize was almost right, at 4:39 you can see that within the Ubuntu (not /mnt) part, default permissions are used. e.g.: `ls -l proc` reveals that much of it is read only. If the Ubuntu on Windows personality/subsystem gave Linux processes full permissions to /mnt/c, I'd expect that would be a security vulnerability, and I'd assume they are doing some mapping. Unfortunately, in the video they posted I never see them do `ls -l` on `/mnt/c`, only a subdirectory they created.