Thanks @clivesj again for this great contrib module.
Since we have a complicated CMS system, the client wants to prevent the certain roles from accessing Drupal private file system path. So we need to separate the access right of the directory listing based on the role.
Please see the screenshot attached.
Closed: won't fix
3.0
Administrative Interface
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
I want to try to prevent adding too much features that serves a very specific task or user requirement.
I would suggest that you make a small module and apply hook_node_access to apply your specific permissions.
I will close this now, please let me know if you need any assistance.