diff --git a/conf/preferencesdialog.cpp b/conf/preferencesdialog.cpp
--- a/conf/preferencesdialog.cpp
+++ b/conf/preferencesdialog.cpp
@@ -25,6 +25,7 @@
     : KConfigDialog( parent, QStringLiteral("preferences"), skeleton )
 {
     setWindowModality( Qt::ApplicationModal );
+    resize(width(), 850);
 
     m_general = new DlgGeneral( this, embedMode );
     m_performance = new DlgPerformance( this );