diff --git a/src/slic3r/GUI/NotificationManager.cpp b/src/slic3r/GUI/NotificationManager.cpp
index 8ee9d4a2c..f7458cab2 100644
--- a/src/slic3r/GUI/NotificationManager.cpp
+++ b/src/slic3r/GUI/NotificationManager.cpp
@@ -9,6 +9,7 @@
 #include "libslic3r/Config.hpp"
 #include "../Utils/PrintHost.hpp"
 #include "libslic3r/Config.hpp"
+#include "format.hpp"
 
 #include <boost/algorithm/string.hpp>
 #include <boost/log/trivial.hpp>