Time zone bug with UTC

I have WordPress set to UTC+2:
Universal time is 2022-04-19 10:00:43. Local time is 2022-04-19 12:00:43.

When I add an event as a full day event, with start and end date as the same day, it still spans over 2 days in the calendar view. If I add it spanning over 2 days, the calendar shows it as 3 days.

If I instead add it as starting 00.00 and ending 23.59 it still spans 2 days, same thing if I set it to end 23.00. But; if I let it en 22.00 it will only show for one day.

When adding the events i let the default Time Zone: UTC+2 in the post admin be.

Conclusion: There is a bug with using UTC times, since exactly those two hours triggers the timing bug.

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