I have an external SSD with several partitions, one of which doesn't show in Path Finder's sidebar (though it does in Finder). I've narrowed it down to a permissions problem: in Disk Utility the other partitions show 'Ownership: Disabled', but this partition it says 'Enabled'.

So I tried to change permissions. The other partitions show:
(Me) Read & write
staff Read & write
everyone Read only
but this partition shows:
System Read & write
wheel Read only
everyone Read only
so I...

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