Some chapters of my translated edition kept their titles in the original language. How do I translate them?

This happened when the original chapter's text had no title line at its top, for example a chapter that started straight with the story or with a plain "Chapter 2: ..." line. The translation took the title only from that line, so those chapters kept the original title. From version 1.9.23 the title comes from the book itself, so new translations get every title in the edition's language. For an edition you translated before, open the original book's page and, in the Editions card, press the re-translate button next to the edition: its tooltip says how many chapter titles are still in the original language. Only the titles are translated again; your translated chapters stay as they are.