Clicking on an appointment only open the calendar app not the appointment

On an appointment in the date time indicator click on one. This I would expect to then open in the calendar app view for the appointment. What actually happens is it open the month view.

<https://wiki.ubuntu.com/TimeAndDate#menu-events>: "If the calendar source is an application, each event should be sensitive, and choosing it in the menu should open the application to edit that event."