All day calendar events not working

Ther have been several similar issues posted here but I couldn’t find a definite answer whether they should work, do work, or don’t work.
I have set up several custom calendars and they all work find as long as I don’t specify an all-day event. All day events are simply not recognized at all. The configuation is as follow:

  - platform: caldav
    url: https://xxx/baikal/html/cal.php/calendars/homeassistant/default
    username: xxx
    password: xxx
      - name: shower
        calendar: Rooms
        search: Shower

The event looks as follows:

<VCALENDAR| [<VERSION{}2.0>, <PRODID{}-//K Desktop Environment//NONSGML libkcal 4.3//EN>, <VEVENT| [<UID{}0ca981cf-425d-4e6d-b96b-7d86f62449e4>, <DTSTART{'VALUE': ['DATE']}2021-03-01>, <DTEND{'VALUE': ['DATE']}2021-03-02>, <CREATED{}2021-03-14 10:47:39+00:00>, <DTSTAMP{}2021-03-19 19:52:05+00:00>, <LAST-MODIFIED{}2021-03-19 19:52:05+00:00>, <RRULE{}FREQ=DAILY>, <SEQUENCE{}6>, <SUMMARY{}Shower>, <TRANSP{}OPAQUE>]>, <X-KDE-ICAL-IMPLEMENTATION-VERSION{}1.0>]>

and if I do a search with the caldav module for today I get

VEVENT| [<UID{}0ca981cf-425d-4e6d-b96b-7d86f62449e4>, <RECURRENCE-ID{'VALUE': ['DATE']}2021-03-19>, <DTSTART{'VALUE': ['DATE']}2021-03-19>, <DTEND{'VALUE': ['DATE']}2021-03-20>, <CREATED{}2021-03-14 10:47:39+00:00>, <DTSTAMP{}2021-03-19 19:52:05+00:00>, <LAST-MODIFIED{}2021-03-19 19:52:05+00:00>, <SEQUENCE{}6>, <SUMMARY{}Shower>, <TRANSP{}OPAQUE>]>

Still Home Assistant won’t recognize the event. If I create an event from 00:00:00 until 00:00:00 the next day and set that repeating every day it works. Except that the calendar goes off for a few minutes around midnight which screws things up.