IDR scanned invoices cannot be viewed in a custom inquiry role

Summary:

HI - we have custom roles defined. We are introducing IDR and the scanned invoices cannot be seen by users that have inquiry only role. We checked and added the privilege AP_VIEW_SCANNED_PAYABLES_INVOICES_PRIV to our custom role, but this is not working.

Seems I need to add - AP_VIEW_SCANNED_PAYABLES_INVOICES_PRIV_OBI to my role, but I cannot add this to the Inquiry role. the Add privilege to role button is disabled:

Any ideas - or is this privilege meant for only maintenance roles - meaning Edit - Update - etc.

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