Chapter settings to merge. For shared dress guidance, PATCH the dress chapter with show_gender_labels: false. Set true to restore labels. Chapter prose strings support selected-text links as label. This applies to standfirst, masthead.subhead, letter/stay/travel/custom body paragraphs, closing.note and guestbook.prompt, including their translations. Only HTTP(S) destinations without credentials, spaces or control characters are links; other markup stays literal text. Strings retain this notation in API reads and writes. Render text and validated links separately, never as raw HTML. For the travel chapter, photo_position is above-description (default) or below-description. Below places the optional photo after the standfirst and body paragraphs, before the airport list. Omit to keep the saved position; set null to restore the default. No photo means no image or extra spacing. For the masthead chapter, show_rsvp_button is an optional boolean, off when absent. True adds a cover link to RSVP on standard Aisle covers when the current viewer can access RSVP. Omit to preserve the setting; false or null turns it off. Read-only shared links and disabled RSVP never show it. Brief retains its existing RSVP link without adding a second button; custom HTML covers are unchanged.