diff --git a/src/board/UBBoardView.cpp b/src/board/UBBoardView.cpp
index 135f1b40..3071dc82 100644
--- a/src/board/UBBoardView.cpp
+++ b/src/board/UBBoardView.cpp
@@ -146,7 +146,8 @@ void UBBoardView::init ()
   setHorizontalScrollBarPolicy (Qt::ScrollBarAlwaysOff);
   setAcceptDrops (true);
 
-  setOptimizationFlag (QGraphicsView::IndirectPainting); // enable UBBoardView::drawItems filter
+  setOptimizationFlags (QGraphicsView::IndirectPainting | QGraphicsView::DontSavePainterState); // enable UBBoardView::drawItems filter
+  setViewportUpdateMode(QGraphicsView::SmartViewportUpdate);
 
   mTabletStylusIsPressed = false;
   mMouseButtonIsPressed = false;
diff --git a/src/domain/UBGraphicsStrokesGroup.cpp b/src/domain/UBGraphicsStrokesGroup.cpp
index b371becd..f5a48d61 100644
--- a/src/domain/UBGraphicsStrokesGroup.cpp
+++ b/src/domain/UBGraphicsStrokesGroup.cpp
@@ -201,7 +201,7 @@ QVariant UBGraphicsStrokesGroup::itemChange(GraphicsItemChange change, const QVa
     return QGraphicsItemGroup::itemChange(change, newValue);
 }
 
-QPainterPath UBGraphicsStrokesGroup::shape () const
+QPainterPath UBGraphicsStrokesGroup::shape() const
 {
     QPainterPath path;