diff --git a/src/slic3r/GUI/GUI_Preview.cpp b/src/slic3r/GUI/GUI_Preview.cpp
index c2a59b5d50..739ed367ce 100644
--- a/src/slic3r/GUI/GUI_Preview.cpp
+++ b/src/slic3r/GUI/GUI_Preview.cpp
@@ -483,7 +483,7 @@ void Preview::update_layers_slider_mode()
                 can_change_color = false;
         }
         // check if whole model uses just only one extruder
-        if (plate_extruders.size() > 1) {
+        if (!plate_extruders.empty()) {
             //const int extruder = objects[0]->config.has("extruder") ? objects[0]->config.option("extruder")->getInt() : 0;
             only_extruder = plate_extruders[0];
         //    auto is_one_extruder_printed_model = [objects, extruder]() {