diff --git a/xs/src/libslic3r/PrintConfig.hpp b/xs/src/libslic3r/PrintConfig.hpp
index b837bb735..74b850326 100644
--- a/xs/src/libslic3r/PrintConfig.hpp
+++ b/xs/src/libslic3r/PrintConfig.hpp
@@ -154,8 +154,8 @@ class StaticPrintConfig : public PrintConfigBase, public StaticConfig
 class PrintObjectConfig : public virtual StaticPrintConfig
 {
     public:
-	ConfigOptionBool                adaptive_slicing;
-	ConfigOptionPercent             adaptive_slicing_quality;
+    ConfigOptionBool                adaptive_slicing;
+    ConfigOptionPercent             adaptive_slicing_quality;
     ConfigOptionBool                dont_support_bridges;
     ConfigOptionFloatOrPercent      extrusion_width;
     ConfigOptionFloatOrPercent      first_layer_height;