Node object custom properties can be edited and set on the 'edit node page'.
Interface object custom properties can be edited and set on the 'edit interface page'.
Volume object custom properties can be edited and set on the 'edit volume page'.
Application object custom properties can be edited and set on the 'edit application page'.
Alert object custom properties can be edited and set on the 'edit alert page'.
So why is it I cannot edit transaction object custom properties from the 'edit transaction page'?
