Background of the issue:
I originally created the website in Polish and translated everything into German and English. I set German as the default language and made many changes on various subpages in German. I want to enable translations from German to Polish because many elements in Polish no longer work.
Symptoms:
I get a message saying that I cannot translate elements that were already translated from Polish to German.
Questions:
How can I set German as the source language for translations?
How can I translate from German to Polish and English, ignoring the current Polish content?
