diff --git a/include/ui.h b/include/ui.h
index d17fc0e..23a248a 100644
--- a/include/ui.h
+++ b/include/ui.h
@@ -167,6 +167,7 @@ void ui_set_stack(int mode);
 void ui_send_internal_notification(const char *message);
 void ui_close_internal_notification(void);
 void ui_toggle_sidebar();
+void ui_toggle_run_edit(int mode);
 
 //
 // Graphical stuff
diff --git a/src/ui/application.c b/src/ui/application.c
index 8745389..07a8f32 100644
--- a/src/ui/application.c
+++ b/src/ui/application.c
@@ -113,6 +113,7 @@ static void gem_graph_client_application_init(GemGraphClientApplication *self)
     ui_disable_action("runmode");
     ui_disable_action("presentmode");
     ui_disable_action("togglesidebar");
+    ui_disable_action("toggle_run_edit");
 }
 
 void ui_send_notification(const char *message)
diff --git a/src/ui/events.c b/src/ui/events.c
index 3f84ffa..3dd9f98 100644
--- a/src/ui/events.c
+++ b/src/ui/events.c
@@ -89,6 +89,19 @@ void on_togglesidebar_action(GSimpleAction *action,
     ui_toggle_sidebar();
 }
 
+void on_toggle_run_stop_action(GSimpleAction *action,
+                    GVariant *parameter,
+                    gpointer user_data)
+{
+    GemGraphClientApplication *self = user_data;
+
+    g_assert(GEM_GRAPH_CLIENT_IS_APPLICATION(self));
+
+    // Switch on the first letter of the mode, because switch is soooo simple :)
+    if      (EDIT_MODE) ui_toggle_run_edit (RUN_MODE);
+    else if (RUN_MODE)  ui_toggle_run_edit (EDIT_MODE);
+}
+
 void on_editmode_action(GSimpleAction *action,
                     GVariant *parameter,
                     gpointer user_data)
@@ -166,6 +179,7 @@ void on_closefile_action(GSimpleAction *action,
     ui_disable_action("editmode");
     ui_disable_action("presentmode");
     ui_disable_action("togglesidebar");
+    ui_disable_action("toggle_run_edit");
     ui_set_stack(HOME_MODE);
 }
 
@@ -362,6 +376,7 @@ void ui_model_loading(GObject *source_object,
     ui_enable_action("editmode");
     ui_enable_action("presentmode");
     ui_enable_action("togglesidebar");
+    ui_enable_action("toggle_run_edit");
     ui_set_stack(RUN_MODE);
 
     g_free(basenamestr);
@@ -397,6 +412,7 @@ void ui_debug_model_loading (GtkWindow *self, const char *file)
     ui_enable_action("editmode");
     ui_enable_action("presentmode");
     ui_enable_action("togglesidebar");
+    ui_enable_action("toggle_run_edit");
     ui_set_stack(RUN_MODE);
     ui_toggle_sidebar();
 }
diff --git a/src/ui/gemgraph.ui b/src/ui/gemgraph.ui
index 31fe3e1..f0785f8 100644
--- a/src/ui/gemgraph.ui
+++ b/src/ui/gemgraph.ui
@@ -19,6 +19,20 @@
             <property name="menu-model">main_menu</property>
           </object>
         </child>
+
+        <!-- On to us a child is born ... -->
+        <child>
+          <object class="GtkToggleButton" id="main_button_run_edit">
+            <property name="icon-name">system-run-symbolic</property>
+            <property name="tooltip-text" translatable="yes">Run mode</property>
+            <property name="action-name">app.toggle_run_edit</property>
+            <!-- applications should be compiled with the -Wl,--export-dynamic argument inside their compiler flags -->
+            <!-- and linked against gmodule-export-2.0 -->
+            <!-- https://docs.gtk.org/gtk4/class.Builder.html -->
+            <!--signal name="clicked" handler="ui_toggle_run_edit"      on_toggle_run_stop_action   /-->
+           </object>
+        </child>
+
         <child type="start">
           <object class="GtkMenuButton" id="main_button_mode">
             <property name="always-show-arrow">True</property>
@@ -33,10 +47,6 @@
             <property name="icon-name">sidebar-show-symbolic</property>
             <property name="tooltip-text" translatable="yes">Display/hide sidebar</property>
             <property name="action-name">app.togglesidebar</property>
-            <!-- applications should be compiled with the -Wl,--export-dynamic argument inside their compiler flags -->
-            <!-- and linked against gmodule-export-2.0 -->
-            <!-- https://docs.gtk.org/gtk4/class.Builder.html -->
-            <!--signal name="clicked" handler="ui_toggle_sidebar" /-->
            </object>
         </child>
       </object>
diff --git a/src/ui/window.c b/src/ui/window.c
index 6192a30..ecda1c2 100644
--- a/src/ui/window.c
+++ b/src/ui/window.c
@@ -45,6 +45,7 @@ struct _GemGraphClientWindow
     GtkStack *side_stack;
     GtkPaned *main_paned;
     GtkMenuButton *main_button_mode;
+    GtkToggleButton *main_button_run_stop;
     GtkToggleButton *main_button_sidebar;
     GtkRevealer *toast_revealer;
     GtkToggleButton *toast_close_button;
@@ -83,6 +84,7 @@ static void gem_graph_client_window_class_init(GemGraphClientWindowClass *klass)
     gtk_widget_class_bind_template_child(widget_class, GemGraphClientWindow, main_stack);
     gtk_widget_class_bind_template_child(widget_class, GemGraphClientWindow, side_stack);
     gtk_widget_class_bind_template_child(widget_class, GemGraphClientWindow, main_paned);
+    gtk_widget_class_bind_template_child(widget_class, GemGraphClientWindow, main_button_run_stop);
     gtk_widget_class_bind_template_child(widget_class, GemGraphClientWindow, main_button_mode);
     gtk_widget_class_bind_template_child(widget_class, GemGraphClientWindow, main_button_sidebar);
     gtk_widget_class_bind_template_child(widget_class, GemGraphClientWindow, toast_revealer);
@@ -194,3 +196,33 @@ void ui_toggle_sidebar(void)
         gtk_paned_set_position(window->main_paned, 400);
     }
 }
+void ui_toggle_run_edit(int mode)
+{
+    if (window->main_stack == NULL) {
+        g_printerr("Can't find self->main_stack !\n");
+        return;
+    }
+    if (window->side_stack == NULL) {
+        g_printerr("Can't find self->side_stack !\n");
+        return;
+    }
+
+    // Switch on the first letter of the mode, because switch is soooo simple :)
+    switch(mode) {
+        case EDIT_MODE:
+       //     gtk_stack_set_visible_child_full(window->main_stack, "edition", GTK_STACK_TRANSITION_TYPE_CROSSFADE);
+            gtk_stack_set_visible_child_full(window->side_stack, "edition", GTK_STACK_TRANSITION_TYPE_CROSSFADE);
+            gtk_menu_button_set_icon_name(window->main_button_run_stop, "document-edit-symbolic");
+            ui_setup_glarea(EDIT_MODE, GTK_WIDGET(window->edition_glarea_box));
+            break;
+        case RUN_MODE:
+        //    gtk_stack_set_visible_child_full(window->main_stack, "run", GTK_STACK_TRANSITION_TYPE_CROSSFADE);
+            gtk_stack_set_visible_child_full(window->side_stack, "run", GTK_STACK_TRANSITION_TYPE_CROSSFADE);
+            gtk_menu_button_set_icon_name(window->main_button_run_stop, "system-run-symbolic");
+            ui_setup_glarea(RUN_MODE, GTK_WIDGET(window->run_glarea_box));
+            ui_create_tree (GTK_WIDGET (window->run_conditions_tree_box));
+            break;
+        default:
+            break;
+    }
+}