diff --git a/gtk/gtkfontbutton.c b/gtk/gtkfontbutton.c
index 4dd63c107c..091ecbfe19 100644
--- a/gtk/gtkfontbutton.c
+++ b/gtk/gtkfontbutton.c
@@ -59,11 +59,11 @@
  *
  * # CSS nodes
  *
- * |[<!-- language="plain" -->
+ * ```
  * fontbutton
  * ╰── button.font
  *     ╰── [content]
- *]|
+ * ```
  *
  * `GtkFontButton` has a single CSS node with name fontbutton which
  * contains a button node with the .font style class.