diff --git a/src/gui/kernel/qwindow.cpp b/src/gui/kernel/qwindow.cpp
index 13da58e391..6dcc3df166 100644
--- a/src/gui/kernel/qwindow.cpp
+++ b/src/gui/kernel/qwindow.cpp
@@ -1751,7 +1751,10 @@ void QWindow::showFullScreen()
 {
     setWindowState(Qt::WindowFullScreen);
     setVisible(true);
+#if !defined Q_OS_QNX // On QNX this window will be activated anyway from libscreen
+                      // activating it here before libscreen activates it causes problems
     requestActivate();
+#endif
 }
 
 /*!
diff --git a/src/widgets/kernel/qwidget.cpp b/src/widgets/kernel/qwidget.cpp
index 03655639d5..5bcec13238 100644
--- a/src/widgets/kernel/qwidget.cpp
+++ b/src/widgets/kernel/qwidget.cpp
@@ -2837,7 +2837,10 @@ void QWidget::showFullScreen()
     setWindowState((windowState() & ~(Qt::WindowMinimized | Qt::WindowMaximized))
                    | Qt::WindowFullScreen);
     setVisible(true);
+#if !defined Q_OS_QNX // On QNX this window will be activated anyway from libscreen
+                      // activating it here before libscreen activates it causes problems
     activateWindow();
+#endif
 }
 
 /*!