Trying to work around 3D scene focus after de-activation of the main

window without having to resort to CallAfter(), which breaks
on Linux with some window managers that follow mouser cursor.
May fix #5620 #6870 #6992

src/slic3r/GUI/Plater.hpp

@@ -149,6 +149,16 @@ public:
     void render_project_state_debug_window() const;
 #endif // ENABLE_PROJECT_DIRTY_STATE_DEBUG_WINDOW
 
+#if defined(__linux__) || defined(_WIN32)
+	// wxWidgets callback to enable / disable window and all its children windows.
+	// called by wxProgressDialog when entering / leaving modal dialog loop.
+	// Unfortunately the wxProgressDialog calls Enable(true) after the wxEVT_ACTIVATE event is processed
+	// while MainFrame is not yet enabled, thus restoring focus in OnActivate() handler fails
+	// and we need to do it now.
+    bool Enable(bool enable) override;
+    void restore_keyboard_focus();
+#endif
+
     Sidebar& sidebar();
     const Model& model() const;
     Model& model();