This is somewhere between a bug and an issue…..
When using the Calendar view in ‘monthly’ mode, if you have more than 5-ish items on a day, they are not all visible and there doesn’t seem to be a method of viewing them, i.e. a scroll bar on the right side of that day in the calendar.
Also, the left edge of items in that day are cropped and should at least appear in full if hovered over (as opposed to having to click each individually to see it’s contents).