diff --git a/avogadro/qtplugins/coloropacitymap/coloropacitymap.cpp b/avogadro/qtplugins/coloropacitymap/coloropacitymap.cpp
index 2198c02ad1..42d72b17e7 100644
--- a/avogadro/qtplugins/coloropacitymap/coloropacitymap.cpp
+++ b/avogadro/qtplugins/coloropacitymap/coloropacitymap.cpp
@@ -8,10 +8,10 @@
 #include "histogramwidget.h"
 
 #include <QAction>
+#include <QDebug>
 #include <QDialog>
 #include <QMessageBox>
 #include <QString>
-#include <QDebug>
 
 #include <avogadro/core/crystaltools.h>
 #include <avogadro/core/cube.h>
@@ -84,6 +84,18 @@ QStringList ColorOpacityMap::menuPath(QAction*) const
   return QStringList() << tr("&Extensions");
 }
 
+void ColorOpacityMap::setActiveWidget(QWidget* widget)
+{
+  auto vtkWidget = qobject_cast<VTK::vtkGLWidget*>(widget);
+  if (vtkWidget) {
+    m_vtkWidget = true;
+    updateActions();
+  } else {
+    m_vtkWidget = false;
+    updateActions();
+  }
+}
+
 void ColorOpacityMap::setMolecule(QtGui::Molecule* mol)
 {
   if (m_molecule == mol)
@@ -114,9 +126,8 @@ void ColorOpacityMap::moleculeChanged(unsigned int c)
 
 void ColorOpacityMap::updateActions()
 {
-  // Just leave it enabled, if you click on it it will be empty...
   foreach (QAction* action, m_actions)
-    action->setEnabled(true);
+    action->setEnabled(m_vtkWidget);
 }
 
 void ColorOpacityMap::updateHistogram()
@@ -124,6 +135,9 @@ void ColorOpacityMap::updateHistogram()
   auto widget = ActiveObjects::instance().activeWidget();
   auto vtkWidget = qobject_cast<VTK::vtkGLWidget*>(widget);
 
+  if (vtkWidget == nullptr)
+    m_vtkWidget = false;
+
   if (widget && vtkWidget && widget != m_activeWidget) {
     if (m_activeWidget)
       disconnect(widget, nullptr, this, nullptr);
@@ -132,6 +146,7 @@ void ColorOpacityMap::updateHistogram()
   }
 
   if (vtkWidget && m_molecule && m_molecule->cubeCount()) {
+    m_vtkWidget = true;
     vtkNew<vtkTable> table;
     auto imageData = vtkWidget->imageData();
     auto lut = vtkWidget->lut();
diff --git a/avogadro/qtplugins/coloropacitymap/coloropacitymap.h b/avogadro/qtplugins/coloropacitymap/coloropacitymap.h
index 725fe6c326..463fc59f60 100644
--- a/avogadro/qtplugins/coloropacitymap/coloropacitymap.h
+++ b/avogadro/qtplugins/coloropacitymap/coloropacitymap.h
@@ -31,6 +31,8 @@ public slots:
 
   void moleculeChanged(unsigned int changes);
 
+  void setActiveWidget(QWidget* widget) override;
+
 private slots:
   void updateActions();
 
@@ -48,6 +50,7 @@ private slots:
   HistogramWidget* m_histogramWidget = nullptr;
   QScopedPointer<QAction> m_displayDialogAction;
 
+  bool m_vtkWidget = false;
   QWidget* m_activeWidget = nullptr;
 };