Clearly show or highlight invoices that have comments, especially from external approvers.

In all inboxes, clearly show whether or not an invoice has a comment.  Often an external approver (client) will add a comment which is very important to know prior to payment.  Currently you have to go into each and every invoice to see if there is a comment prior to paying.  If there was a "I" for internal comments and an "E" for external user comments beside each row, that would save much time.