Display of Holidays in KOrganizer: All national and all (?) regional holidays in Germany missing for at least 2024

I am referring here to my KOrganizer installation (version 24.08.1-1) as part of KDE PIM/Kontact in my Majnaro installation.

Behavior:

a) All national holidays in Germany and

b) all regional holidays for the specific federal state of Germany my calendar in KOrganizer refers to

are not displayed for at least the current year 2024 as holidays in red and bold formatted day numbers in KOrganizer in the “Day”, “Week” and “Month” view.

Instead, these holidays are displayed in black and non-bold formatted (i.e. as standard) numbers in my calendar.

My calendar is an ical calendar file I had imported several weeks ago from my PIM installation under Debian 12 (“Bookworm”, current stable release) into KDE PIM in my Manjaro installation.

In my Manjaro installation, this imported ical calendar is set as the default calendar in KOrganizer. In my KDE PIM installation under Debian 12, all national and regional holidays in Germany are displayed in red and bold formatted numbers.

My KDE installation in Manjaro is configured as follows:

a) Package “kdepim-addons” is installed.

b) Digital Clock Settings (accessible via the time and date module in the KDE Task Bar):

  • “Calendar” section at the left: The following options under “Available Plugins” have been selected: a) “Holidays”, b) “Calendar Events”
  • “Holidays” section at the left: The following options have been selected: a) “Germany, ”, b) “Germany”

c) In KOrganizer settings:

  • “Time and Date” section at the left: The “Holidays” selection field has been set to “Germany (German), (German)”

Wouldn´t this here be an issue to be resolved by the respective Linux distributor, thus in this case by the maintainers of the Manjaro project?

If every single Manjaro user would be expected to solve this problem on his/her own, how should he/she do that? Which KDE configuration files to edit and so on?