Translate month-name in the date-field

[Shel]

I searched for how to display the names in the panel date-field for the months, for example May / Mai, in German. (how) is this possible, or is this still relevant:

Panel date not showing month name in my locale

The dates in the Panel (date edit) always show the English month name. I have almost changed everything I could think off. I have set the user language → this will change the months language only in the popup calendar for date selection. I have changed my browser language in system settings (macOS) → nothing changed in the date fields language still English. I have not been able to find a setting in Herd to change a language. (I examined every file from ‘open configuration files’ in Herd) I h…

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