diff --git a/src/ui/tree.c b/src/ui/tree.c
index 5a1224d..1aea984 100644
--- a/src/ui/tree.c
+++ b/src/ui/tree.c
@@ -53,6 +53,16 @@ create_and_fill_model (void)
 
   /* Append a top level row and leave it empty */
   gtk_tree_store_append(treestore, &toplevel, NULL);
+  gtk_tree_store_set(treestore, &toplevel,
+                     COL_FIRST_NAME, "RanTanPlan",
+                     COL_LAST_NAME, "(dog)",
+                     -1);
+
+  gtk_tree_store_append(treestore, &toplevel, NULL);
+  gtk_tree_store_set(treestore, &toplevel,
+                     COL_FIRST_NAME, "Ma",
+                     COL_LAST_NAME, "Dalton",
+                     -1);
 
   /* Append a second top level row, and fill it with some data */
   gtk_tree_store_append(treestore, &toplevel, NULL);
@@ -61,6 +71,18 @@ create_and_fill_model (void)
                      COL_LAST_NAME, "Dalton",
                      -1);
 
+  gtk_tree_store_append(treestore, &toplevel, NULL);
+  gtk_tree_store_set(treestore, &toplevel,
+                     COL_FIRST_NAME, "Jack",
+                     COL_LAST_NAME, "Dalton",
+                     -1);
+
+  gtk_tree_store_append(treestore, &toplevel, NULL);
+  gtk_tree_store_set(treestore, &toplevel,
+                     COL_FIRST_NAME, "William",
+                     COL_LAST_NAME, "Dalton",
+                     -1);
+
   /* Append a child to the second top level row, and fill in some data */
   gtk_tree_store_append(treestore, &child, &toplevel);
   gtk_tree_store_set(treestore, &child,
@@ -176,11 +198,8 @@ tree_c_test(void)
 static void tree_c_printing_test(void)
 {
     printf("tree.c  tree_c_printing_test()   \
-------------------------------------\n\
-A button is now in the  GtkBox *runlib_objects of windows.c (line 61)\n\
-              How to associate an action to it\n\
-                            ?\n\
-");
+-------------------------------\n\
+A button is now in the GtkBox and an action is associated to it.\n\n");
 }
 
 /*
diff --git a/src/ui/window.c b/src/ui/window.c
index 107a698..0dca17b 100644
--- a/src/ui/window.c
+++ b/src/ui/window.c
@@ -124,7 +124,6 @@ void ui_set_stack(const char *mode)
             break;
         case 'r':
             gtk_menu_button_set_icon_name(window->main_button_mode, "system-run-symbolic");
-//            create_tree_label();
             create_tree_button();
             break;
         case 'p':
@@ -243,14 +242,17 @@ GtkWidget *create_tree_label(void)
     return label;
 }
 
+
+
 #include <gtk/gtk.h>
 
 static void
 print_hello (GtkWidget *widget,
              gpointer   data)
 {
-    printf("Yes.  I'm the new button   <->   I've been clicked !!!\n");
-//    return GDK_EVENT_STOP;
+    static int nb;
+    nb++;
+    printf("Button clicked  (n = %d)\n", nb);
 }
 
 GtkWidget *create_tree_button(void)
@@ -263,10 +265,10 @@ GtkWidget *create_tree_button(void)
     gtk_widget_show(button);
 
     g_signal_connect (button, "clicked", G_CALLBACK (print_hello), NULL);
-    //g_signal_connect_swapped (button, "clicked", G_CALLBACK (gtk_window_destroy), window);
 
     tree_c_test();
 
     return button;
 }
 
+/* https://docs.gtk.org/gtk4/getting_started.html */