I noticed that the thin beam for all-day-appointments in your calendar appears not only, when an appointment takes from 00:00 to 00:00 of the next day, but also if an appointment is longer than 24 hours.
For example:
If an appointment starts today at 13:00 oclock and ends tomorrow at 14:00 oclock, the cal recognizes this as a all-day-appointment for today AND tomorrow and shows its all-day-beam for these two days.
But its not a all-day-event for even one of these two days.
If I set the end time of this appointment back to 12:30 the event shows in cal like a normal event.
I noticed that the thin beam for all-day-appointments in your calendar appears not only, when an appointment takes from 00:00 to 00:00 of the next day, but also if an appointment is longer than 24 hours. For example: If an appointment starts today at 13:00 oclock and ends tomorrow at 14:00 oclock, the cal recognizes this as a all-day-appointment for today AND tomorrow and shows its all-day-beam for these two days. But its not a all-day-event for even one of these two days. If I set the end time of this appointment back to 12:30 the event shows in cal like a normal event.