When an appointment is pending, a small indicator appears in the taskbar at the height of the calendar applet

beju
  1 month ago
  0
  Under review

My idea concerns the Cinnamon desktop calendar applet (calendar@cinnamon.org):
A small indicator appearing in the bar (e.g. a dot or similar), which - depending on feasibility also user-defined - is displayed at the beginning or before the beginning of an event.