diff --git a/callback.c b/callback.c
index eef1fe4..824197d 100644
--- a/callback.c
+++ b/callback.c
@@ -51,6 +51,7 @@ void ui_toggle_exec_edit (GtkWidget *btt_exec_xor_edit, gpointer data)
     set_exec_edit_mode (0);
   } else {
     gtk_button_set_icon_name (GTK_BUTTON (btt_exec_xor_edit), "document-edit-symbolic");
+    gtk_button_set_icon_name (GTK_BUTTON (btt_exec_xor_edit), "text-editor-symbolic"); // I hesitate
     set_exec_edit_mode (1);
   }
 }
@@ -62,7 +63,17 @@ void ui_toggle_model_exec (GtkWidget *btt_run_stop_model_exec, gpointer data)
     set_run_xor_stop_exec (0);
   } else {
     gtk_button_set_icon_name (GTK_BUTTON (btt_run_stop_model_exec), "media-playback-pause-symbolic");
+//  gtk_button_set_icon_name (GTK_BUTTON (btt_run_stop_model_exec), "system-shutdown-symbolic");
+//  I hesitate :  The button should then toggle between activable xor inactivable states
     set_run_xor_stop_exec (1);
   }
 }
 
+void ui_model_exec_depends_on_edition (GtkWidget *btt_run_stop_model_exec, gpointer data)
+{
+  if (get_run_xor_stop_exec() && get_exec_edit_mode()) {
+    gtk_button_set_icon_name (GTK_BUTTON (btt_run_stop_model_exec), "media-playback-start-symbolic");
+//    set_run_xor_stop_exec (0);
+  }
+}
+
diff --git a/callback.h b/callback.h
index 19391b4..4ba19f2 100644
--- a/callback.h
+++ b/callback.h
@@ -10,8 +10,9 @@ void ui_disable_action (const char *name);
 //  @see  application . gem_graph_client_application_init (GemGraphClientApplication *self) {
 //        g_action_map_add_action_entries (G_ACTION_MAP(self), app_actions, G_N_ELEMENTS(app_actions), self); ...
 
-void ui_toggle_exec_edit ();
-void ui_toggle_model_exec ();
+void ui_toggle_exec_edit     (GtkWidget *btt_exec_xor_edit, gpointer data);
+void ui_toggle_model_exec    (GtkWidget *btt_run_stop_model_exec, gpointer data);
+void ui_model_exec_depends_on_edition (GtkWidget *btt_run_stop_model_exec, gpointer data);
 
 void on_quit_action          (GSimpleAction *action, GVariant *parameter, gpointer user_data);
 void on_about_action         (GSimpleAction *action, GVariant *parameter, gpointer user_data);
diff --git a/contain.c b/contain.c
index 7d34115..e1baab8 100644
--- a/contain.c
+++ b/contain.c
@@ -287,6 +287,7 @@ void window_header_bar (GtkWindow *window, char *title){
   gtk_button_set_icon_name (exec_xor_edit, "text-editor-symbolic");
   gtk_button_set_icon_name (exec_xor_edit, "system-run-symbolic");
   g_signal_connect (exec_xor_edit, "clicked", G_CALLBACK (ui_toggle_exec_edit), NULL);
+  g_signal_connect (exec_xor_edit, "clicked", G_CALLBACK (ui_model_exec_depends_on_edition), NULL);
   gtk_header_bar_pack_start (GTK_HEADER_BAR (header_bar), GTK_WIDGET (exec_xor_edit));
 
   gtk_window_set_titlebar (window, header_bar);
diff --git a/display.c b/display.c
index 936c56c..32280dd 100644
--- a/display.c
+++ b/display.c
@@ -111,8 +111,8 @@ GtkBox *get_RUN_STOP_box(){
 GtkBox *get_ZOOM_box(){
   GtkBox *ZOOM_box = GTK_BOX (gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0));
   GtkWidget *ZOOM_Label = GTK_WIDGET (gtk_label_new (\
-    "\n   TOOLS\n      ---\n   zoom\n      ---\n   (space\n   struct.)\n\
-      ---\n   (arrows\n   struct.)\n"));
+    "\n   TOOLS\n      ---\n   zoom\n      ---\n   space\n   struct.\n\
+      ---\n  arrows\n   struct.\n      ---\n   orient\n    state\n in space\n"));
   gtk_widget_set_size_request (GTK_WIDGET (ZOOM_box), 10, 80);
   gtk_box_append (ZOOM_box, ZOOM_Label);
   return ZOOM_box;