Fix start minimized to tray for unix

src/core/Bootstrap.cpp

@@ -106,7 +106,11 @@ namespace Bootstrap
     {
         // start minimized if configured
         if (config()->get("GUI/MinimizeOnStartup").toBool()) {
+#ifdef Q_OS_WIN
             mainWindow.showMinimized();
+#else
+            mainWindow.hideWindow();
+#endif
         } else {
             mainWindow.bringToFront();
         }