Fullcalender multi-day event is one day too short

Hi,
When showing events in FullCalendar view, multi-day events are one day too short. For example:
Start time: 2022-12-10 00:00:00
End time: 2022-12-11 23:55:00

Should appear on December 10 and 11, 2022. However, in the Month/Week/Day views of FullCalendar, the event only appears on the 10th. I have activated the option "Show All Days Of Multiple Days Event In Calendar" under Configuration->Themes. Everything works properly in the old Calendar view - it's only a problem in FullCalendar.

Thanks