diff --git a/gtk/gtkcolorbutton.c b/gtk/gtkcolorbutton.c
index f4f8cc40fb..622cce0b60 100644
--- a/gtk/gtkcolorbutton.c
+++ b/gtk/gtkcolorbutton.c
@@ -58,8 +58,15 @@
  *
  * # CSS nodes
  *
- * GtkColorButton has a single CSS node with name button. To differentiate
- * it from a plain #GtkButton, it gets the .color style class.
+ * |[<!-- language="plain" -->
+ * colorbutton
+ * ╰── button.color
+ *     ╰── [content]
+ *]|
+ *
+ * GtkColorButton has a single CSS node with name colorbutton which
+ * contains a button node. To differentiate it from a plain #GtkButton,
+ * it gets the .color style class.
  */
 
 typedef struct _GtkColorButtonClass     GtkColorButtonClass;
diff --git a/gtk/gtkfontbutton.c b/gtk/gtkfontbutton.c
index dc842eb737..50f86feb54 100644
--- a/gtk/gtkfontbutton.c
+++ b/gtk/gtkfontbutton.c
@@ -59,7 +59,14 @@
  *
  * # CSS nodes
  *
- * GtkFontButton has a single CSS node with name fontbutton.
+ * |[<!-- 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.
  */
 
 typedef struct _GtkFontButtonClass   GtkFontButtonClass;
diff --git a/gtk/gtkmenubutton.c b/gtk/gtkmenubutton.c
index d37ee47fc1..29a320aff3 100644
--- a/gtk/gtkmenubutton.c
+++ b/gtk/gtkmenubutton.c
@@ -104,8 +104,14 @@
  *
  * # CSS nodes
  *
- * GtkMenuButton has a single CSS node with name button. To differentiate
- * it from a plain #GtkButton, it gets the .popup style class.
+ * |[<!-- language="plain" -->
+ * menubutton
+ * ╰── button.toggle
+ *     ╰── [content]
+ *]|
+ *
+ * GtkMenuButton has a single CSS node with name menubutton
+ * which contains a toggle button node.
  *
  * # Accessibility
  *
diff --git a/gtk/gtkmodelbutton.c b/gtk/gtkmodelbutton.c
index b6ce026da9..d01b0dba3b 100644
--- a/gtk/gtkmodelbutton.c
+++ b/gtk/gtkmodelbutton.c
@@ -489,7 +489,7 @@ update_node_name (GtkModelButton *self)
     {
     case GTK_BUTTON_ROLE_TITLE:
       start_name = "arrow";
-      end_name = NULL;
+      end_name = "";
       break;
     case GTK_BUTTON_ROLE_NORMAL:
       start_name = NULL;