diff --git a/src/3rdparty/qtsingleapplication/qtlocalpeer.h b/src/3rdparty/qtsingleapplication/qtlocalpeer.h
index 684dfe8b1..352976978 100644
--- a/src/3rdparty/qtsingleapplication/qtlocalpeer.h
+++ b/src/3rdparty/qtsingleapplication/qtlocalpeer.h
@@ -27,6 +27,8 @@
 **
 ****************************************************************************/
 
+#pragma once
+
 #include <qtlockedfile.h>
 
 #include <QLocalServer>