Fixed imgui out of synch with mouse after switching between preview and 3D view

src/slic3r/GUI/GLCanvas3D.cpp

@@ -4527,14 +4527,6 @@ void GLCanvas3D::_resize(unsigned int w, unsigned int h)
     if (m_canvas == nullptr && m_context == nullptr)
         return;
 
-#if ENABLE_SCROLLABLE_LEGEND
-    const std::array<unsigned int, 2> new_size = { w, h };
-    if (m_old_size == new_size)
-        return;
-
-    m_old_size = new_size;
-#endif // ENABLE_SCROLLABLE_LEGEND
-
     auto *imgui = wxGetApp().imgui();
     imgui->set_display_size(static_cast<float>(w), static_cast<float>(h));
     const float font_size = 1.5f * wxGetApp().em_unit();

src/slic3r/GUI/GLCanvas3D.hpp

@@ -425,10 +425,6 @@ private:
     Model* m_model;
     BackgroundSlicingProcess *m_process;
 
-#if ENABLE_SCROLLABLE_LEGEND
-    std::array<unsigned int, 2> m_old_size{ 0, 0 };
-#endif // ENABLE_SCROLLABLE_LEGEND
-
     // Screen is only refreshed from the OnIdle handler if it is dirty.
     bool m_dirty;
     bool m_initialized;