I know someone who was asked to translate an Ibsen play (can't remember which one) to serve as a basis for someone else to produce a stage version. She said she wasn't credited but she didn't care at the time because it was the first literary translation job she'd ever had and that the theatre people were surprised how much swearing there was in her version compared to previous translations.

I have never seen any Ibsen and I didn't do it at university because he was combined with Strindberg and we were painfully reading Röda Rummet round the class in Swedish lessons at the time and that was quite enough of him. I did 1950s and 1960s Scandinavian literature in which everyone was mad instead.