diff --git a/gtk/gtkassistant.c b/gtk/gtkassistant.c
index 2e77f1cece..5cf57b0bbb 100644
--- a/gtk/gtkassistant.c
+++ b/gtk/gtkassistant.c
@@ -106,6 +106,7 @@ struct _GtkAssistantPrivate
   GtkWidget *last;
 
   GtkWidget *sidebar;
+  GtkWidget *sidebar_frame;
   GtkWidget *content;
   GtkWidget *action_area;
 
@@ -440,6 +441,7 @@ gtk_assistant_class_init (GtkAssistantClass *class)
   gtk_widget_class_bind_template_child_private (widget_class, GtkAssistant, close);
   gtk_widget_class_bind_template_child_private (widget_class, GtkAssistant, last);
   gtk_widget_class_bind_template_child_private (widget_class, GtkAssistant, sidebar);
+  gtk_widget_class_bind_template_child_private (widget_class, GtkAssistant, sidebar_frame);
   gtk_widget_class_bind_template_child_private (widget_class, GtkAssistant, button_size_group);
   gtk_widget_class_bind_template_child_private (widget_class, GtkAssistant, title_size_group);
 
@@ -747,7 +749,7 @@ update_title_state (GtkAssistant *assistant)
         show_titles = TRUE;
     }
 
-  gtk_widget_set_visible (priv->sidebar, show_titles);
+  gtk_widget_set_visible (priv->sidebar_frame, show_titles);
 }
 
 static void