diff --git a/plugins/dockers/overview/overviewdocker_dock.cpp b/plugins/dockers/overview/overviewdocker_dock.cpp
index 2cfa57a2bc..23940a0701 100644
--- a/plugins/dockers/overview/overviewdocker_dock.cpp
+++ b/plugins/dockers/overview/overviewdocker_dock.cpp
@@ -1,154 +1,156 @@
 /*
  *  Copyright (c) 2009 Cyrille Berger <cberger@cberger.net>
  *
  *  This library is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU Lesser General Public License as published by
  *  the Free Software Foundation; version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This library is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public License
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
 #include "overviewdocker_dock.h"
 #include "overviewwidget.h"
 
 #include <QLabel>
 #include <QVBoxLayout>
 #include <QHBoxLayout>
 #include <QToolButton>
 #include <QStatusBar>
 #include <kis_slider_spin_box.h>
 #include <klocalizedstring.h>
 
 #include "kis_canvas2.h"
 #include <KisViewManager.h>
 #include <kactioncollection.h>
 #include <kis_action.h>
 #include <kis_zoom_manager.h>
 #include "kis_image.h"
 #include "kis_paint_device.h"
 #include "kis_signal_compressor.h"
 #include "kis_canvas_controller.h"
 #include "kis_icon_utils.h"
 #include "kis_signals_blocker.h"
 
 OverviewDockerDock::OverviewDockerDock( )
     : QDockWidget(i18n("Overview"))
     , m_zoomSlider(nullptr)
     , m_rotateSlider(nullptr)
     , m_mirrorCanvas(nullptr)
     , m_canvas(nullptr)
 {
     QWidget *page = new QWidget(this);
     m_layout = new QVBoxLayout(page);
     m_horizontalLayout = new QHBoxLayout();
 
     m_overviewWidget = new OverviewWidget(this);
     m_overviewWidget->setMinimumHeight(50);
     m_overviewWidget->setBackgroundRole(QPalette::AlternateBase);
     m_overviewWidget->setAutoFillBackground(true); // paints background role before paint()
 
     m_layout->addWidget(m_overviewWidget, 1);
 
     setWidget(page);
 }
 
 void OverviewDockerDock::setCanvas(KoCanvasBase * canvas)
 {
     if(m_canvas == canvas)
         return;
 
     setEnabled(canvas != nullptr);
 
     if (m_canvas) {
         m_canvas->disconnectCanvasObserver(this);
         m_canvas->image()->disconnect(this);
     }
 
     if (m_zoomSlider) {
         m_layout->removeWidget(m_zoomSlider);
         delete m_zoomSlider;
         m_zoomSlider = nullptr;
     }
 
     if (m_rotateSlider) {
         m_horizontalLayout->removeWidget(m_rotateSlider);
         delete m_rotateSlider;
         m_rotateSlider = nullptr;
     }
 
     if (m_mirrorCanvas) {
         m_horizontalLayout->removeWidget(m_mirrorCanvas);
         delete m_mirrorCanvas;
         m_mirrorCanvas = nullptr;
     }
 
     m_layout->removeItem(m_horizontalLayout);
 
     m_canvas = dynamic_cast<KisCanvas2*>(canvas);
 
     m_overviewWidget->setCanvas(canvas);
     if (m_canvas && m_canvas->viewManager() && m_canvas->viewManager()->zoomController() && m_canvas->viewManager()->zoomController()->zoomAction()) {
         m_zoomSlider = m_canvas->viewManager()->zoomController()->zoomAction()->createWidget(m_canvas->imageView()->KisView::statusBar());
         m_layout->addWidget(m_zoomSlider);
 
         m_rotateSlider = new KisDoubleSliderSpinBox();
         m_rotateSlider->setRange(-180, 180, 2);
         m_rotateSlider->setValue(m_canvas->rotationAngle());
         m_rotateSlider->setPrefix(i18n("Rotation: "));
         m_rotateSlider->setSuffix("°");
         connect(m_rotateSlider, SIGNAL(valueChanged(qreal)), this, SLOT(rotateCanvasView(qreal)), Qt::UniqueConnection);
         connect(m_canvas->canvasController()->proxyObject, SIGNAL(canvasOffsetXChanged(int)), this, SLOT(updateSlider()));
 
         m_mirrorCanvas = new QToolButton();
         QList<QAction *> actions = m_canvas->viewManager()->actionCollection()->actions();
         Q_FOREACH(QAction* action, actions) {
             if (action->objectName()=="mirror_canvas") {
                 m_mirrorCanvas->setDefaultAction(action);
             }
         }
         m_horizontalLayout->addWidget(m_mirrorCanvas);
         m_horizontalLayout->addWidget(m_rotateSlider);
         m_layout->addLayout(m_horizontalLayout);
     }
 }
 
 void OverviewDockerDock::unsetCanvas()
 {
     setEnabled(false);
     m_canvas = nullptr;
     m_overviewWidget->unsetCanvas();
 }
 
 void OverviewDockerDock::rotateCanvasView(qreal rotation)
 {
+    if (!m_canvas) return;
     KisCanvasController *canvasController =
             dynamic_cast<KisCanvasController*>(m_canvas->viewManager()->canvasBase()->canvasController());
     if (canvasController) {
         canvasController->rotateCanvas(rotation-m_canvas->rotationAngle());
     }
 }
 
 void OverviewDockerDock::updateSlider()
 {
+    if (!m_canvas) return;
     KisSignalsBlocker l(m_rotateSlider);
 
     qreal rotation = m_canvas->rotationAngle();
     if (rotation > 180) {
         rotation = rotation - 360;
     } else if (rotation < -180) {
         rotation = rotation + 360;
     }
     if (m_rotateSlider->value() != rotation) {
         m_rotateSlider->setValue(rotation);
     }
 }