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When creating an event on the calendar, there is a separate tab called "Description" with 1 small, lonely, text box, also called Description.
I suggest moving this small text box to the Event tab for convenience. Having it on a separate tab, it will never get used. If someone did write something there, you would never see it unless you clicked the Description tab every time you looked at an event (not likely).
Also, looks like every event has "No Description" written inside the Description text box. Leaving the field empty would be fine.