MSW specific: Fixed update of the UI after system color change.

Note: the wxEVT_SYS_COLOUR_CHANGED event works only for high contrast settings under MSW.

+ ConfigSnapshotDialog: Fixed UI colors for dark mode on all platforms

src/slic3r/GUI/MainFrame.cpp

@@ -522,6 +522,8 @@ void MainFrame::init_tabpanel()
 #ifndef __WXOSX__ // Don't call SetFont under OSX to avoid name cutting in ObjectList
     m_tabpanel->SetFont(Slic3r::GUI::wxGetApp().normal_font());
 #endif
+    if (wxSystemSettings::GetAppearance().IsDark())
+        m_tabpanel->SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOW));
     m_tabpanel->Hide();
     m_settings_dialog.set_tabpanel(m_tabpanel);
 
@@ -838,6 +840,9 @@ void MainFrame::on_sys_color_changed()
 
     // update label colors in respect to the system mode
     wxGetApp().init_label_colours();
+#ifdef __WXMSW__
+    m_tabpanel->SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOW));
+#endif
 
     // update Plater
     wxGetApp().plater()->sys_color_changed();