diff --git a/kcmkwin/kwinscreenedges/kwinscreenedge.h b/kcmkwin/kwinscreenedges/kwinscreenedge.h
--- a/kcmkwin/kwinscreenedges/kwinscreenedge.h
+++ b/kcmkwin/kwinscreenedges/kwinscreenedge.h
@@ -72,7 +72,7 @@
     virtual bool isSaveNeeded() const;
     virtual bool isDefault() const;
 
-    // internal use, assert if border equals ELECTRIC_COUNT or ElectricNone
+    // internal use, return Monitor::None if border equals ELECTRIC_COUNT or ElectricNone
     static int electricBorderToMonitorEdge(ElectricBorder border);
     static ElectricBorder monitorEdgeToElectricBorder(int edge);
 
diff --git a/kcmkwin/kwinscreenedges/kwinscreenedge.cpp b/kcmkwin/kwinscreenedges/kwinscreenedge.cpp
--- a/kcmkwin/kwinscreenedges/kwinscreenedge.cpp
+++ b/kcmkwin/kwinscreenedges/kwinscreenedge.cpp
@@ -168,7 +168,7 @@
     case ElectricTopLeft:
         return Monitor::TopLeft;
     default: // ELECTRIC_COUNT and ElectricNone
-        Q_ASSERT(false);
+        return Monitor::None;
     }
 }
 
diff --git a/kcmkwin/kwinscreenedges/monitor.h b/kcmkwin/kwinscreenedges/monitor.h
--- a/kcmkwin/kwinscreenedges/monitor.h
+++ b/kcmkwin/kwinscreenedges/monitor.h
@@ -67,7 +67,8 @@
         TopLeft,
         TopRight,
         BottomLeft,
-        BottomRight
+        BottomRight,
+        None
     };
 Q_SIGNALS:
     void changed();