niculskin does not take german language with weewx > 4.5.1

[Astrid]

Hello!

I am using weewx with niculskin and highcharts.

In skin.conf at niculskin folder I have:

[Language]

    #
    # Set a language below and labels will be overridden with any that are specified in
    # skins/languages/[language].conf
    #
    # Choices are: dutch, espanol, finnish, francais, italian, german

    language = german

I am using suse leap 15.3 rpm for weewx.

Up to version 4.5.1 of weewx all is ok.

But with version > 4.5.1 (e.g. 4.7) it always take english language

for generating all pages.

How can I get it work with german language?

Regards, Astrid