diff --git a/src/slic3r/GUI/GUI_Preview.cpp b/src/slic3r/GUI/GUI_Preview.cpp
index 119eb2ed5..134da4848 100644
--- a/src/slic3r/GUI/GUI_Preview.cpp
+++ b/src/slic3r/GUI/GUI_Preview.cpp
@@ -1242,17 +1242,13 @@ void Preview::load_print_as_fff(bool keep_z_range)
     }
 
 #if ENABLE_GCODE_VIEWER
-    if (wxGetApp().is_editor() && !has_layers)
-#else
-    if (! has_layers)
-#endif // ENABLE_GCODE_VIEWER
-    {
-#if ENABLE_GCODE_VIEWER
+    if (wxGetApp().is_editor() && !has_layers) {
         hide_layers_slider();
         m_left_sizer->Hide(m_bottom_toolbar_panel);
         m_left_sizer->Layout();
         Refresh();
 #else
+    if (! has_layers) {
         reset_sliders(true);
         m_canvas->reset_legend_texture();
 #endif // ENABLE_GCODE_VIEWER
@@ -1260,8 +1256,7 @@ void Preview::load_print_as_fff(bool keep_z_range)
         return;
     }
 
-    if (m_preferred_color_mode == "tool_or_feature")
-    {
+    if (m_preferred_color_mode == "tool_or_feature") {
         // It is left to Slic3r to decide whether the print shall be colored by the tool or by the feature.
         // Color by feature if it is a single extruder print.
         unsigned int number_extruders = (unsigned int)print->extruders().size();
@@ -1290,31 +1285,32 @@ void Preview::load_print_as_fff(bool keep_z_range)
     std::vector<CustomGCode::Item> color_print_values = {};
     // set color print values, if it si selected "ColorPrint" view type
 #if ENABLE_GCODE_VIEWER
-    if (gcode_view_type == GCodeViewer::EViewType::ColorPrint)
+    if (gcode_view_type == GCodeViewer::EViewType::ColorPrint) {
 #else
-    if (m_gcode_preview_data->extrusion.view_type == GCodePreviewData::Extrusion::ColorPrint)
+    if (m_gcode_preview_data->extrusion.view_type == GCodePreviewData::Extrusion::ColorPrint) {
 #endif // ENABLE_GCODE_VIEWER
-    {
         colors = wxGetApp().plater()->get_colors_for_color_print();
 #if !ENABLE_GCODE_VIEWER
         colors.push_back("#808080"); // gray color for pause print or custom G-code 
 #endif // !ENABLE_GCODE_VIEWER
 
-        if (!gcode_preview_data_valid)
+        if (!gcode_preview_data_valid) {
             color_print_values = wxGetApp().plater()->model().custom_gcode_per_print_z.gcodes;
+#if ENABLE_GCODE_VIEWER
+            colors.push_back("#808080"); // gray color for pause print or custom G-code 
+#endif // ENABLE_GCODE_VIEWER
+        }
     }
 #if ENABLE_GCODE_VIEWER
-    else if (gcode_preview_data_valid || gcode_view_type == GCodeViewer::EViewType::Tool)
+    else if (gcode_preview_data_valid || gcode_view_type == GCodeViewer::EViewType::Tool) {
 #else
-    else if (gcode_preview_data_valid || (m_gcode_preview_data->extrusion.view_type == GCodePreviewData::Extrusion::Tool) )
+    else if (gcode_preview_data_valid || (m_gcode_preview_data->extrusion.view_type == GCodePreviewData::Extrusion::Tool) ) {
 #endif // ENABLE_GCODE_VIEWER
-    {
         colors = wxGetApp().plater()->get_extruder_colors_from_plater_config();
         color_print_values.clear();
     }
 
-    if (IsShown())
-    {
+    if (IsShown()) {
 #if ENABLE_GCODE_VIEWER
         std::vector<double> zs;
 #endif // ENABLE_GCODE_VIEWER