msdosfs and cd9660 are the only filesystems that verify the filesystem
type in the label. This is the wrong place, sanity checks should only
rely on the inner structure of the filesystem (like signatures or
magic numbers).
msdosfs also used the device type information from the label to
deduce a filesystem parameter heuristically for the gemdos variant.
If there is no information inside the filesystem data itself, this
should be an explicit mount option.
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