diff --git a/src/widgets/kernel/qwidget_qpa.cpp b/src/widgets/kernel/qwidget_qpa.cpp
index 289b332a13..c0dbf0497e 100644
--- a/src/widgets/kernel/qwidget_qpa.cpp
+++ b/src/widgets/kernel/qwidget_qpa.cpp
@@ -483,7 +483,15 @@ void QWidgetPrivate::hide_sys()
 
 void QWidgetPrivate::setMaxWindowState_helper()
 {
-    setFullScreenSize_helper(); //### decoration size
+    Q_Q(QWidget);
+
+    const uint old_state = data.in_set_window_state;
+    data.in_set_window_state = 1;
+
+    const QRect desktop = qApp->desktop()->availableGeometry(qApp->desktop()->screenNumber(q));
+    q->setGeometry(desktop);
+
+    data.in_set_window_state = old_state;
 }
 
 void QWidgetPrivate::setFullScreenSize_helper()