diff --git a/gtk/gtkexpander.c b/gtk/gtkexpander.c
index 3b71c92d10..85e2b67e1f 100644
--- a/gtk/gtkexpander.c
+++ b/gtk/gtkexpander.c
@@ -96,10 +96,11 @@
  *
  * |[<!-- language="plain" -->
  * expander
- * ├── title
- * │   ├── arrow
- * │   ╰── <label widget>
- * ╰── <child>
+ * ╰── box
+ *     ├── title
+ *     │   ├── arrow
+ *     │   ╰── <label widget>
+ *     ╰── <child>
  * ]|
  *
  * GtkExpander has three CSS nodes, the main node with the name expander,