diff --git a/GUI/Model/Item/RectangularDetectorItem.cpp b/GUI/Model/Item/RectangularDetectorItem.cpp
index f1b5f0208f3b9e3c43104d19d2b8ace5395d3ec9..e236f2c62a4554f95aab40e3ea0de57d458d81f8 100644
--- a/GUI/Model/Item/RectangularDetectorItem.cpp
+++ b/GUI/Model/Item/RectangularDetectorItem.cpp
@@ -109,10 +109,8 @@ void RectangularDetectorItem::serialize(Serializer& s)
     s.rw(m_v0);
     s.rw(m_distance);
 
-    if (s.isReading()) {
-        m_detectorAlignment = static_cast<RectangularDetector::EDetectorArrangement>(alignment);
-        updateTooltips();
-    }
+    if (s.isReading())
+        setDetectorAlignment(static_cast<RectangularDetector::EDetectorArrangement>(alignment));
 }
 
 void RectangularDetectorItem::setDetectorAlignment(
diff --git a/GUI/View/Instrument/InstrumentLibraryEditor.cpp b/GUI/View/Instrument/InstrumentLibraryEditor.cpp
index 1c9b5e785ca36aa7c039ef998d3dd49ed96f8a42..2953f62fddb7dcb0ce4b34a1f4af749485f148e0 100644
--- a/GUI/View/Instrument/InstrumentLibraryEditor.cpp
+++ b/GUI/View/Instrument/InstrumentLibraryEditor.cpp
@@ -129,6 +129,7 @@ void InstrumentLibraryEditor::execAdd(const InstrumentItem& instrumentToAdd)
     m_ui->buttonBox->button(QDialogButtonBox::Cancel)->hide();
 
     QModelIndex index = m_treeModel->indexForItem(addedInstrument);
+    m_ui->treeView->expandAll();
     m_ui->treeView->setCurrentIndex(index);
     m_ui->treeView->scrollTo(index, QAbstractItemView::PositionAtTop);
     setModal(true);
diff --git a/GUI/View/PlotUtil/IntensityDataPropertyWidget.cpp b/GUI/View/PlotUtil/IntensityDataPropertyWidget.cpp
index 9b2322307677f3c0a1d08814c1cf8b92362b498c..d804fd9f9c92b4bb00324930ae325f3c73c06e60 100644
--- a/GUI/View/PlotUtil/IntensityDataPropertyWidget.cpp
+++ b/GUI/View/PlotUtil/IntensityDataPropertyWidget.cpp
@@ -99,6 +99,8 @@ void IntensityDataPropertyWidget::setItem(IntensityDataItem* item)
     // react on external changes (e.g. zooming in customplot shall update the axis values)
     item->mapper()->setOnChildPropertyChange(
         [=](SessionItem*, const QString&) { updateUIValues(); }, this);
+
+    item->mapper()->setOnItemDestroy([this](SessionItem*) { m_item = nullptr; }, this);
 }
 
 QWidget* IntensityDataPropertyWidget::createDoubleSpinbox(DoubleDescriptor d)