diff --git a/synfig-studio/src/gui/canvasview.cpp b/synfig-studio/src/gui/canvasview.cpp
index 3904e3e..cb55c91 100644
--- a/synfig-studio/src/gui/canvasview.cpp
+++ b/synfig-studio/src/gui/canvasview.cpp
@@ -868,7 +868,13 @@ CanvasView::~CanvasView()
 	App::dock_manager->unregister_dockable(*this);
 	signal_deleted()();
 
-	App::ui_manager()->remove_action_group(action_group);
+	// I didn't find a proper way to check if actiongroup is already removed on CanvasView::deactivate
+	// So here is a quick-hack. This error is mostly invisible because it fails on App exiting
+	// but i didn't think it worth to spend time to it, because remove_action_group is deprecated
+	// and this code is required to rewrite.
+	
+	if (!this->_action_group_removed) 
+		App::ui_manager()->remove_action_group(action_group);
 
 	// Shut down the smach
 	smach_.egress();
@@ -909,6 +915,7 @@ void CanvasView::activate()
 	activation_index_.activate();
 	get_smach().process_event(EVENT_REFRESH_TOOL_OPTIONS);
 	App::ui_manager()->insert_action_group(action_group);
+	this->_action_group_removed = false;
 	update_title();
 	present();
 }
@@ -917,6 +924,7 @@ void CanvasView::deactivate()
 {
 	get_smach().process_event(EVENT_YIELD_TOOL_OPTIONS);
 	App::ui_manager()->remove_action_group(action_group);
+	this->_action_group_removed = true;
 	update_title();
 }
 
diff --git a/synfig-studio/src/gui/canvasview.h b/synfig-studio/src/gui/canvasview.h
index a0573ba..97e97ee 100644
--- a/synfig-studio/src/gui/canvasview.h
+++ b/synfig-studio/src/gui/canvasview.h
@@ -409,6 +409,7 @@ private:
 	Gtk::RadioButtonGroup low_res_pixel_size_group;
 
 	Glib::RefPtr<Gtk::ActionGroup> action_group;
+	bool _action_group_removed;
 
 	etl::handle<synfigapp::UIInterface> ui_interface_;
 	etl::handle<synfigapp::SelectionManager> selection_manager_;
diff --git a/synfig-studio/src/gui/docks/dockbook.cpp b/synfig-studio/src/gui/docks/dockbook.cpp
index 9440c04..0537d1a 100644
--- a/synfig-studio/src/gui/docks/dockbook.cpp
+++ b/synfig-studio/src/gui/docks/dockbook.cpp
@@ -87,15 +87,30 @@ DockBook::DockBook():
 
 DockBook::~DockBook()
 {
-	DockManager::containers_to_remove_.erase(this);
 	deleting_=true;
 	clear();
+	DockManager::containers_to_remove_.erase(this);
 }
 
 void
 DockBook::clear()
 {
-	while(get_n_pages())
+	// here the point: get_n_pages is fails because this is not notebook type
+	// i didn't know why this happens, possibly because clear() is called from destructor
+	// and 'this' is already deleted. Or, this function maybe never work right.
+	// So here quick-hack again. Btw, as you can see from commented code later newly created 
+	// dockbook is works fine, so this situation is reqired more detailed investigation.
+	if (!GTK_IS_NOTEBOOK (this)) return; // because we always fail if 'this' is not notebook
+
+	/*Gtk::Notebook note;
+	int x = note.get_n_pages();
+
+	DockBook db;
+	x = db.get_n_pages();
+
+	const Gtk::Notebook* nb = (const Gtk::Notebook*)this;*/
+	//assert(GTK_IS_NOTEBOOK (nb));
+	while (this->get_n_pages())
 		remove(static_cast<Dockable&>(*get_nth_page(get_n_pages()-1)));
 }