diff --git a/kcmkwin/kwindecoration/preview.cpp b/kcmkwin/kwindecoration/preview.cpp
index 04a91dd967..13aa005127 100644
--- a/kcmkwin/kwindecoration/preview.cpp
+++ b/kcmkwin/kwindecoration/preview.cpp
@@ -118,13 +118,11 @@ void KDecorationPreview::render(QPainter *painter, KDecoration *decoration, cons
     int padLeft, padRight, padTop, padBottom;
     padLeft = padRight = padTop = padBottom = 0;
     bool useMask = true;
-    if (KDecorationUnstable *unstable = qobject_cast<KDecorationUnstable *>(decoration)) {
-        unstable->padding(padLeft, padRight, padTop, padBottom);
-        size.setWidth(size.width() + padLeft + padRight);
-        size.setHeight(size.height() + padTop + padBottom);
-        if (padLeft || padRight || padTop || padBottom) {
-            useMask = false;
-        }
+    decoration->padding(padLeft, padRight, padTop, padBottom);
+    size.setWidth(size.width() + padLeft + padRight);
+    size.setHeight(size.height() + padTop + padBottom);
+    if (padLeft || padRight || padTop || padBottom) {
+        useMask = false;
     }
     decoration->resize(size);
 
@@ -479,11 +477,10 @@ KDecorationPreviewOptions::~KDecorationPreviewOptions()
 {
 }
 
-unsigned long KDecorationPreviewOptions::updateSettings()
+void KDecorationPreviewOptions::updateSettings()
 {
     KConfig cfg("kwinrc");
-    unsigned long changed = 0;
-    changed |= KDecorationOptions::updateSettings(&cfg);
+    KDecorationOptions::updateSettings(&cfg);
 
     // set custom border size/buttons
     if (customBorderSize != BordersCount)
@@ -499,8 +496,6 @@ unsigned long KDecorationPreviewOptions::updateSettings()
         setTitleButtonsLeft(KDecorationOptions::defaultTitleButtonsLeft());
         setTitleButtonsRight(KDecorationOptions::defaultTitleButtonsRight());
     }
-
-    return changed;
 }
 
 void KDecorationPreviewOptions::setCustomBorderSize(BorderSize size)
diff --git a/kcmkwin/kwindecoration/preview.h b/kcmkwin/kwindecoration/preview.h
index 6e322d44e7..0a5c734b3b 100644
--- a/kcmkwin/kwindecoration/preview.h
+++ b/kcmkwin/kwindecoration/preview.h
@@ -60,7 +60,7 @@ private:
 };
 
 class KDecorationPreviewBridge
-    : public KDecorationBridgeUnstable
+    : public KDecorationBridge
 {
 public:
     KDecorationPreviewBridge(KDecorationPreview* preview, bool active);
@@ -139,7 +139,7 @@ class KDecorationPreviewOptions
 public:
     KDecorationPreviewOptions();
     virtual ~KDecorationPreviewOptions();
-    virtual unsigned long updateSettings();
+    void updateSettings();
 
     void setCustomBorderSize(BorderSize size);
     void setCustomTitleButtonsEnabled(bool enabled);