diff --git a/src/workspace.cpp b/src/workspace.cpp
index 9f6d59065c..74f4e94467 100644
--- a/src/workspace.cpp
+++ b/src/workspace.cpp
@@ -2427,9 +2427,7 @@ void Workspace::desktopResized()
 
 void Workspace::saveOldScreenSizes()
 {
-    olddisplaysize = m_geometry.size();
     m_oldScreenGeometries.clear();
-
     for (const Output *output : std::as_const(m_outputs)) {
         m_oldScreenGeometries.insert(output, output->geometry());
     }
@@ -2715,16 +2713,6 @@ QHash<const Output *, QRect> Workspace::previousScreenSizes() const
     return m_oldScreenGeometries;
 }
 
-int Workspace::oldDisplayWidth() const
-{
-    return olddisplaysize.width();
-}
-
-int Workspace::oldDisplayHeight() const
-{
-    return olddisplaysize.height();
-}
-
 Output *Workspace::xineramaIndexToOutput(int index) const
 {
     xcb_connection_t *connection = kwinApp()->x11Connection();
diff --git a/src/workspace.h b/src/workspace.h
index ba01d5382f..5fb0cd651d 100644
--- a/src/workspace.h
+++ b/src/workspace.h
@@ -306,8 +306,6 @@ public:
     bool inUpdateClientArea() const;
     StrutRects previousRestrictedMoveArea(const VirtualDesktop *desktop, StrutAreas areas = StrutAreaAll) const;
     QHash<const Output *, QRect> previousScreenSizes() const;
-    int oldDisplayWidth() const;
-    int oldDisplayHeight() const;
 
     /**
      * Returns the list of windows sorted in stacking order, with topmost window
@@ -743,7 +741,6 @@ private:
     QRect m_geometry;
 
     QHash<const Output *, QRect> m_oldScreenGeometries;
-    QSize olddisplaysize; // previous sizes od displayWidth()/displayHeight()
     QHash<const VirtualDesktop *, StrutRects> m_oldRestrictedAreas;
     bool m_inUpdateClientArea = false;