Windows 11, Indesign 20.1
Problem description: I have six documents, two in German, two in English, two in French. In all six is a paragraph with the same name, but the language setting is according to the document language. Means, the style is set to French (for spelling checker) in the french documents. When copying text by copy & paste from one french document to the others, the language setting of that text in the target document changes to German. This doesn't happen when copying english text from an english document to the other english document, same with the german ones.