diff --git a/placement.cpp b/placement.cpp
index e371c21c4b..13b7ae4476 100644
--- a/placement.cpp
+++ b/placement.cpp
@@ -483,7 +483,7 @@ void Placement::placeUtility(Client* c, QRect& area, Policy /*next*/)
     place(c, area, Default);
 }
 
-void Placement::placeOnScreenDisplay(Client* c, QRect& area)
+void Placement::placeOnScreenDisplay(AbstractClient* c, QRect& area)
 {
     // place at lower 1/3 of the screen
     const int x = area.left() + (area.width() -  c->width())  / 2;
diff --git a/placement.h b/placement.h
index 941f45ff6d..ce0fdf6596 100644
--- a/placement.h
+++ b/placement.h
@@ -72,7 +72,7 @@ public:
     void placeZeroCornered(AbstractClient* c, const QRect& area, Policy next = Unknown);
     void placeDialog(Client* c, QRect& area, Policy next = Unknown);
     void placeUtility(Client* c, QRect& area, Policy next = Unknown);
-    void placeOnScreenDisplay(Client* c, QRect& area);
+    void placeOnScreenDisplay(AbstractClient* c, QRect& area);
 
     void reinitCascading(int desktop);