diff --git a/libdialogutil/dialogstatesaver.cpp b/libdialogutil/dialogstatesaver.cpp
index 93b2a7d..5021374 100644
--- a/libdialogutil/dialogstatesaver.cpp
+++ b/libdialogutil/dialogstatesaver.cpp
@@ -1,143 +1,140 @@
 /************************************************************************
  *									*
  *  This file is part of Kooka, a scanning/OCR application using	*
  *  Qt <http://www.qt.io> and KDE Frameworks <http://www.kde.org>.	*
  *									*
  *  Copyright (C) 2016 Jonathan Marten <jjm@keelhaul.me.uk>		*
  *									*
  *  Kooka is free software; you can redistribute it and/or modify it	*
  *  under the terms of the GNU Library General Public License as	*
  *  published by the Free Software Foundation and appearing in the	*
  *  file COPYING included in the packaging of this file;  either	*
  *  version 2 of the License, or (at your option) any later version.	*
  *									*
  *  As a special exception, permission is given to link this program	*
  *  with any version of the KADMOS OCR/ICR engine (a product of		*
  *  reRecognition GmbH, Kreuzlingen), and distribute the resulting	*
  *  executable without including the source code for KADMOS in the	*
  *  source distribution.						*
  *									*
  *  This program is distributed in the hope that it will be useful,	*
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of	*
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the	*
  *  GNU General Public License for more details.			*
  *									*
  *  You should have received a copy of the GNU General Public		*
  *  License along with this program;  see the file COPYING.  If		*
  *  not, see <http://www.gnu.org/licenses/>.				*
  *									*
  ************************************************************************/
 
 #include "dialogstatesaver.h"
 
 #include <qdialog.h>
-#include <qdesktopwidget.h>
-#include <qapplication.h>
+#include <qwindow.h>
+#include <qscreen.h>
 #include <qdebug.h>
 
 #include <kconfiggroup.h>
 #include <ksharedconfig.h>
 
 
 static bool sSaveSettings = true;
 
 
 DialogStateSaver::DialogStateSaver(QDialog *pnt)
 {
     Q_ASSERT(pnt!=nullptr);
     mParent = pnt;
 }
 
 
 static KConfigGroup configGroupFor(QWidget *window)
 {
     QString objName = window->objectName();
     if (objName.isEmpty())
     {
         objName = window->metaObject()->className();
         qWarning() << "object name not set, using class name" << objName;
     }
     else qDebug() << "for" << objName << "which is a" << window->metaObject()->className();
 
     return (KSharedConfig::openConfig(QString(), KConfig::NoCascade)->group(objName));
 }
 
 
 void DialogStateSaver::restoreConfig()
 {
     if (!sSaveSettings) return;				// settings not to be restored
 
     const KConfigGroup grp = configGroupFor(mParent);
     this->restoreConfig(mParent, grp);
 }
 
 
 void DialogStateSaver::restoreConfig(QDialog *dialog, const KConfigGroup &grp)
 {
     restoreWindowState(dialog, grp);
 }
 
 
 void DialogStateSaver::restoreWindowState(QWidget *window)
 {
     const KConfigGroup grp = configGroupFor(window);
     restoreWindowState(window, grp);
 }
 
 
 void DialogStateSaver::restoreWindowState(QWidget *window, const KConfigGroup &grp)
 {
-    // from KDE4 KDialog::restoreDialogSize()
-    int scnum = QApplication::desktop()->screenNumber(window->parentWidget());
-    QRect desk = QApplication::desktop()->screenGeometry(scnum);
-    int width = window->sizeHint().width();
-    int height = window->sizeHint().height();
+    // originally from KDE4 KDialog::restoreDialogSize()
+    const QRect desk = window->parentWidget()->window()->windowHandle()->screen()->geometry();
+    const QSize sizeDefault = window->sizeHint();
 
     qDebug() << "from" << grp.name() << "in" << grp.config()->name();
-    width = grp.readEntry(QString::fromLatin1("Width %1").arg(desk.width()), width);
-    height = grp.readEntry(QString::fromLatin1("Height %1").arg(desk.height()), height);
+    const int width = grp.readEntry(QString::fromLatin1("Width %1").arg(desk.width()), sizeDefault.width());
+    const int height = grp.readEntry(QString::fromLatin1("Height %1").arg(desk.height()), sizeDefault.height());
     window->resize(width, height);
 }
 
 
 void DialogStateSaver::saveConfig() const
 {
     if (!sSaveSettings) return;				// settings not to be saved
 
     KConfigGroup grp = configGroupFor(mParent);
     this->saveConfig(mParent, grp);
     grp.sync();
 }
 
 
 void DialogStateSaver::saveConfig(QDialog *dialog, KConfigGroup &grp) const
 {
     saveWindowState(dialog, grp);
 }
 
 
 void DialogStateSaver::saveWindowState(QWidget *window)
 {
     KConfigGroup grp = configGroupFor(window);
     saveWindowState(window, grp);
 }
 
 
 void DialogStateSaver::saveWindowState(QWidget *window, KConfigGroup &grp)
 {
-    // from KDE4 KDialog::saveDialogSize()
-    const int scnum = QApplication::desktop()->screenNumber(window->parentWidget());
-    QRect desk = QApplication::desktop()->screenGeometry(scnum);
+    // originally from KDE4 KDialog::saveDialogSize()
+    const QRect desk = window->parentWidget()->window()->windowHandle()->screen()->geometry();
     const QSize sizeToSave = window->size();
 
     qDebug() << "to" << grp.name() << "in" << grp.config()->name();
     grp.writeEntry(QString::fromLatin1("Width %1").arg(desk.width()), sizeToSave.width());
     grp.writeEntry( QString::fromLatin1("Height %1").arg(desk.height()), sizeToSave.height());
     grp.sync();
 }
 
 
 void DialogStateSaver::setSaveSettingsDefault(bool on)
 {
     sSaveSettings = on;
 }