diff --git a/src/GUI/OptionsGroup/UI_Slider.cpp b/src/GUI/OptionsGroup/UI_Slider.cpp
index 5edd3f8a1..de6410d95 100644
--- a/src/GUI/OptionsGroup/UI_Slider.cpp
+++ b/src/GUI/OptionsGroup/UI_Slider.cpp
@@ -1,5 +1,6 @@
 #include "OptionsGroup/Field.hpp"
 #include "misc_ui.hpp"
+#include "utils.hpp"
 
 namespace Slic3r { namespace GUI {