diff --git a/ksmserver/logout.cpp b/ksmserver/logout.cpp
--- a/ksmserver/logout.cpp
+++ b/ksmserver/logout.cpp
@@ -58,12 +58,11 @@
 #endif
 
 #include <QApplication>
-#include <QPushButton>
 #include <QTimer>
 #include <QFile>
-#include <QProcess>
 #include <QFutureWatcher>
 #include <QtConcurrentRun>
+#include <QDesktopWidget>
 
 #include <KConfig>
 #include <KSharedConfig>
@@ -79,11 +78,6 @@
 #include "logoutprompt_interface.h"
 #include "shutdown_interface.h"
 
-#include <QDesktopWidget>
-#include <QX11Info>
-#include <X11/Xutil.h>
-#include <X11/Xatom.h>
-
 void KSMServer::logout( int confirm, int sdtype, int sdmode )
 {
     // KDE5: remove me
@@ -505,8 +499,6 @@
                 startKilling();
             }
         });
-        createLogoutEffectWidget();
-
     } else if ( state == Checkpoint ) {
         foreach( KSMClient* c, clients ) {
             SmsSaveComplete( c->connection());
@@ -561,7 +553,6 @@
 {
     if( state != Killing )
         return;
-    delete logoutEffectWidget;
 
     qCDebug(KSMSERVER) << "Starting killing WM";
     state = KillingWM;
@@ -618,25 +609,6 @@
     killingCompleted();
 }
 
-void KSMServer::createLogoutEffectWidget()
-{
-// Ok, this is rather a hack. In order to fade the whole desktop when playing the logout
-// sound, killing applications and leaving KDE, create a dummy window that triggers
-// the logout fade effect again.
-    logoutEffectWidget = new QWidget( nullptr, Qt::X11BypassWindowManagerHint );
-    logoutEffectWidget->winId(); // workaround for Qt4.3 setWindowRole() assert
-    logoutEffectWidget->setWindowRole( QStringLiteral( "logouteffect" ) );
-
-    // Qt doesn't set this on unmanaged windows
-    //FIXME: or does it?
-    XChangeProperty( QX11Info::display(), logoutEffectWidget->winId(),
-        XInternAtom( QX11Info::display(), "WM_WINDOW_ROLE", False ), XA_STRING, 8, PropModeReplace,
-        (unsigned char *)"logouteffect", strlen( "logouteffect" ));
-
-    logoutEffectWidget->setGeometry( -100, -100, 1, 1 );
-    logoutEffectWidget->show();
-}
-
 void KSMServer::saveSubSession(const QString &name, QStringList saveAndClose, QStringList saveOnly)
 {
     if( state != Idle ) { // performing startup
diff --git a/ksmserver/server.h b/ksmserver/server.h
--- a/ksmserver/server.h
+++ b/ksmserver/server.h
@@ -155,7 +155,6 @@
     void completeKillingWM();
     void cancelShutdown( KSMClient* c );
     void killingCompleted();
-    void createLogoutEffectWidget();
 
     void discardSession();
     void storeSession();
@@ -240,7 +239,6 @@
     QTimer protectionTimer;
     QTimer restoreTimer;
     QString xonCommand;
-    QWidget* logoutEffectWidget;
     // sequential startup
     int appsToStart;
     int lastAppStarted;
diff --git a/ksmserver/server.cpp b/ksmserver/server.cpp
--- a/ksmserver/server.cpp
+++ b/ksmserver/server.cpp
@@ -599,7 +599,6 @@
 KSMServer::KSMServer( const QString& windowManager, InitFlags flags )
   : wmProcess( nullptr )
   , sessionGroup( QStringLiteral( "" ) )
-  , logoutEffectWidget( nullptr )
   , sockets{ -1, -1 }
 {
     if (!flags.testFlag(InitFlag::NoLockScreen)) {