diff --git a/src/slic3r/GUI/MainFrame.cpp b/src/slic3r/GUI/MainFrame.cpp
index ba98bfc470..d98de4e2ba 100644
--- a/src/slic3r/GUI/MainFrame.cpp
+++ b/src/slic3r/GUI/MainFrame.cpp
@@ -2271,6 +2271,8 @@ void MainFrame::on_sys_color_changed()
 #endif
 #endif
 
+    diff_dialog.on_sys_color_changed();
+
     // BBS
     m_tabpanel->Rescale();
     m_param_panel->msw_rescale();
diff --git a/src/slic3r/GUI/UnsavedChangesDialog.hpp b/src/slic3r/GUI/UnsavedChangesDialog.hpp
index e4d7d61092..8a9d9e680c 100644
--- a/src/slic3r/GUI/UnsavedChangesDialog.hpp
+++ b/src/slic3r/GUI/UnsavedChangesDialog.hpp
@@ -463,7 +463,6 @@ public:
 
     std::array<Preset::Type, 3>         types_list() const;
 
-protected:
     void on_dpi_changed(const wxRect& suggested_rect) override;
     void on_sys_color_changed() override;
 };