Fix potential race condition. Closes #4742.

src/app/main.cpp

@@ -354,8 +354,8 @@ void showSplashScreen()
     painter.setFont(QFont("Arial", 22, QFont::Black));
     painter.drawText(224 - painter.fontMetrics().width(version), 270, version);
     QSplashScreen *splash = new QSplashScreen(splash_img);
-    QTimer::singleShot(1500, splash, SLOT(deleteLater()));
     splash->show();
+    QTimer::singleShot(1500, splash, SLOT(deleteLater()));
     qApp->processEvents();
 }
 #endif