diff --git a/src/libslic3r/Technologies.hpp b/src/libslic3r/Technologies.hpp
index 39dd726ce..974037516 100644
--- a/src/libslic3r/Technologies.hpp
+++ b/src/libslic3r/Technologies.hpp
@@ -12,6 +12,7 @@
 // Renders a small sphere in the center of the bounding box of the current selection when no gizmo is active
 #define ENABLE_RENDER_SELECTION_CENTER 0
 
+
 //====================
 // 1.42.0.alpha1 techs
 //====================
@@ -25,6 +26,7 @@
 // Use wxDataViewRender instead of wxDataViewCustomRenderer
 #define ENABLE_NONCUSTOM_DATA_VIEW_RENDERING (0 && ENABLE_1_42_0_ALPHA1)
 
+
 //====================
 // 1.42.0.alpha2 techs
 //====================
@@ -32,7 +34,6 @@
 
 // Adds print bed models to 3D scene
 #define ENABLE_PRINT_BED_MODELS (1 && ENABLE_1_42_0_ALPHA2)
-#endif // _technologies_h_
 
 
 //====================
@@ -61,3 +62,5 @@
 
 // Toolbar items hidden/shown in dependence of the user mode
 #define ENABLE_MODE_AWARE_TOOLBAR_ITEMS (1 && ENABLE_1_42_0_ALPHA5)
+
+#endif // _technologies_h_
diff --git a/src/slic3r/GUI/GLCanvas3D.cpp b/src/slic3r/GUI/GLCanvas3D.cpp
index b70ba60e0..1d63840fa 100644
--- a/src/slic3r/GUI/GLCanvas3D.cpp
+++ b/src/slic3r/GUI/GLCanvas3D.cpp
@@ -366,7 +366,11 @@ const Pointfs& GLCanvas3D::Bed::get_shape() const
 
 bool GLCanvas3D::Bed::set_shape(const Pointfs& shape)
 {
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+    EType new_type = _detect_type(shape);
+#else
     EType new_type = _detect_type();
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
     if (m_shape == shape && m_type == new_type)
         // No change, no need to update the UI.
         return false;
@@ -516,7 +520,11 @@ void GLCanvas3D::Bed::_calc_gridlines(const ExPolygon& poly, const BoundingBox&
         printf("Unable to create bed grid lines\n");
 }
 
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+GLCanvas3D::Bed::EType GLCanvas3D::Bed::_detect_type(const Pointfs& shape) const
+#else
 GLCanvas3D::Bed::EType GLCanvas3D::Bed::_detect_type() const
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
 {
     EType type = Custom;
 
@@ -528,7 +536,27 @@ GLCanvas3D::Bed::EType GLCanvas3D::Bed::_detect_type() const
         {
 			if (curr->config.has("bed_shape"))
 			{
-				if (boost::contains(curr->name, "SL1"))
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+                if ((curr->vendor != nullptr) && (curr->vendor->name == "Prusa Research") && (shape == dynamic_cast<const ConfigOptionPoints*>(curr->config.option("bed_shape"))->values))
+                {
+                    if (boost::contains(curr->name, "SL1"))
+                    {
+                        type = SL1;
+                        break;
+                    }
+                    else if (boost::contains(curr->name, "MK3") || boost::contains(curr->name, "MK2.5"))
+                    {
+                        type = MK3;
+                        break;
+                    }
+                    else if (boost::contains(curr->name, "MK2"))
+                    {
+                        type = MK2;
+                        break;
+                    }
+                }
+#else
+                if (boost::contains(curr->name, "SL1"))
 				{
 					//FIXME add a condition on the size of the print bed?
 					type = SL1;
@@ -549,7 +577,8 @@ GLCanvas3D::Bed::EType GLCanvas3D::Bed::_detect_type() const
 						}
 					}
 				}
-			}
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
+            }
 
             curr = bundle->printers.get_preset_parent(*curr);
         }
@@ -707,6 +736,7 @@ void GLCanvas3D::Bed::_render_custom() const
     }
 }
 
+#if !ENABLE_REWORKED_BED_SHAPE_CHANGE
 bool GLCanvas3D::Bed::_are_equal(const Pointfs& bed_1, const Pointfs& bed_2)
 {
     if (bed_1.size() != bed_2.size())
@@ -720,6 +750,7 @@ bool GLCanvas3D::Bed::_are_equal(const Pointfs& bed_1, const Pointfs& bed_2)
 
     return true;
 }
+#endif // !ENABLE_REWORKED_BED_SHAPE_CHANGE
 
 const double GLCanvas3D::Axes::Radius = 0.5;
 const double GLCanvas3D::Axes::ArrowBaseRadius = 2.5 * GLCanvas3D::Axes::Radius;
@@ -4231,18 +4262,26 @@ void GLCanvas3D::set_bed_shape(const Pointfs& shape)
 {
     bool new_shape = m_bed.set_shape(shape);
 
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+    if (new_shape)
+    {
+        // Set the origin and size for painting of the coordinate system axes.
+        m_axes.origin = Vec3d(0.0, 0.0, (double)GROUND_Z);
+        set_bed_axes_length(0.1 * m_bed.get_bounding_box().max_size());
+        m_requires_zoom_to_bed = true;
+
+        m_dirty = true;
+    }
+#else
     // Set the origin and size for painting of the coordinate system axes.
     m_axes.origin = Vec3d(0.0, 0.0, (double)GROUND_Z);
     set_bed_axes_length(0.1 * m_bed.get_bounding_box().max_size());
 
     if (new_shape)
-#if ENABLE_REWORKED_BED_SHAPE_CHANGE
-        m_requires_zoom_to_bed = true;
-#else
         zoom_to_bed();
-#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
 
     m_dirty = true;
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
 }
 
 void GLCanvas3D::set_bed_axes_length(double length)
@@ -4793,7 +4832,9 @@ void GLCanvas3D::reload_scene(bool refresh_immediately, bool force_full_scene_re
     if (m_reload_delayed)
         return;
 
+#if !ENABLE_REWORKED_BED_SHAPE_CHANGE
     set_bed_shape(dynamic_cast<const ConfigOptionPoints*>(m_config->option("bed_shape"))->values);
+#endif // !ENABLE_REWORKED_BED_SHAPE_CHANGE
 
     if (m_regenerate_volumes)
     {
@@ -5116,17 +5157,21 @@ void GLCanvas3D::on_char(wxKeyEvent& evt)
     // see include/wx/defs.h enum wxKeyCode
     int keyCode = evt.GetKeyCode();
     int ctrlMask = wxMOD_CONTROL;
-#ifdef __APPLE__
-    ctrlMask |= wxMOD_RAW_CONTROL;
-#endif /* __APPLE__ */
+//#ifdef __APPLE__
+//    ctrlMask |= wxMOD_RAW_CONTROL;
+//#endif /* __APPLE__ */
     if ((evt.GetModifiers() & ctrlMask) != 0) {
         switch (keyCode) {
+        case 'a':
+        case 'A':
         case WXK_CONTROL_A: post_event(SimpleEvent(EVT_GLCANVAS_SELECT_ALL)); break;
 #ifdef __APPLE__
         case WXK_BACK: // the low cost Apple solutions are not equipped with a Delete key, use Backspace instead.
+#else /* __APPLE__ */
+        case WXK_DELETE:
 #endif /* __APPLE__ */
-        case WXK_DELETE:    post_event(SimpleEvent(EVT_GLTOOLBAR_DELETE_ALL)); break;
-        default:            evt.Skip();
+                            post_event(SimpleEvent(EVT_GLTOOLBAR_DELETE_ALL)); break;
+		default:            evt.Skip();
         }
     } else if (evt.HasModifiers()) {
         evt.Skip();
@@ -5137,9 +5182,11 @@ void GLCanvas3D::on_char(wxKeyEvent& evt)
         case WXK_ESCAPE: { m_gizmos.reset_all_states(); m_dirty = true;  break; }
 #ifdef __APPLE__
         case WXK_BACK: // the low cost Apple solutions are not equipped with a Delete key, use Backspace instead.
+#else /* __APPLE__ */
+		case WXK_DELETE:
 #endif /* __APPLE__ */
-        case WXK_DELETE: post_event(SimpleEvent(EVT_GLTOOLBAR_DELETE)); break;
-        case '0': { select_view("iso"); break; }
+                  post_event(SimpleEvent(EVT_GLTOOLBAR_DELETE)); break;
+		case '0': { select_view("iso"); break; }
         case '1': { select_view("top"); break; }
         case '2': { select_view("bottom"); break; }
         case '3': { select_view("front"); break; }
diff --git a/src/slic3r/GUI/GLCanvas3D.hpp b/src/slic3r/GUI/GLCanvas3D.hpp
index 84a162082..8da4394c1 100644
--- a/src/slic3r/GUI/GLCanvas3D.hpp
+++ b/src/slic3r/GUI/GLCanvas3D.hpp
@@ -226,6 +226,10 @@ class GLCanvas3D
     public:
         Bed();
 
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+        EType get_type() const { return m_type; }
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
+
         bool is_prusa() const;
         bool is_custom() const;
 
@@ -247,14 +251,20 @@ class GLCanvas3D
         void _calc_bounding_box();
         void _calc_triangles(const ExPolygon& poly);
         void _calc_gridlines(const ExPolygon& poly, const BoundingBox& bed_bbox);
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+        EType _detect_type(const Pointfs& shape) const;
+#else
         EType _detect_type() const;
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
 #if ENABLE_PRINT_BED_MODELS
         void _render_prusa(const std::string &key, float theta, bool useVBOs) const;
 #else
         void _render_prusa(const std::string &key, float theta) const;
 #endif // ENABLE_PRINT_BED_MODELS
         void _render_custom() const;
+#if !ENABLE_REWORKED_BED_SHAPE_CHANGE
         static bool _are_equal(const Pointfs& bed_1, const Pointfs& bed_2);
+#endif // !ENABLE_REWORKED_BED_SHAPE_CHANGE
     };
 
     struct Axes
diff --git a/src/slic3r/GUI/GUI_Preview.cpp b/src/slic3r/GUI/GUI_Preview.cpp
index 0ad6c3562..b06bde411 100644
--- a/src/slic3r/GUI/GUI_Preview.cpp
+++ b/src/slic3r/GUI/GUI_Preview.cpp
@@ -419,6 +419,10 @@ void Preview::reload_print(bool force)
     m_canvas->reset_legend_texture();
     m_loaded = false;
 
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+    m_canvas->set_bed_shape(dynamic_cast<const ConfigOptionPoints*>(m_config->option("bed_shape"))->values);
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
+
     if (!IsShown() && !force)
         return;
 
diff --git a/src/slic3r/GUI/MainFrame.cpp b/src/slic3r/GUI/MainFrame.cpp
index 78dffa1cb..91574cda6 100644
--- a/src/slic3r/GUI/MainFrame.cpp
+++ b/src/slic3r/GUI/MainFrame.cpp
@@ -319,29 +319,33 @@ void MainFrame::init_menubar()
         Bind(wxEVT_UPDATE_UI, [this](wxUpdateUIEvent& evt) { evt.Enable((m_plater != nullptr) && can_slice()); }, m_menu_item_reslice_now->GetId());
     }
 
+#ifdef _MSC_VER
+    // \xA0 is a non-breaking space. It is entered here to spoil the automatic accelerators,
+    // as the simple numeric accelerators spoil all numeric data entry.
+    wxString sep = "\t\xA0";
+    wxString sep_space = "\xA0";
+#else
+    wxString sep = " - ";
+    wxString sep_space = "";
+#endif
+
     // Edit menu
     wxMenu* editMenu = nullptr;
     if (m_plater != nullptr)
     {
         editMenu = new wxMenu();
-        // \xA0 is a non-breaking space. It is entered here to spoil the automatic accelerators,
-        // as the simple numeric accelerators spoil all numeric data entry.
-        wxMenuItem* item_select_all = append_menu_item(editMenu, wxID_ANY, _(L("&Select all")) +
-#ifdef _MSC_VER
-            "\t\xA0" + "Ctrl+\xA0" + "A"
-#else
-#ifdef __APPLE__
-            "\tCtrl+A"
-#else
-            " - Ctrl+A"
-#endif
-#endif
-            , _(L("Selects all objects")),
+    #ifdef __APPLE__
+        // Backspace sign
+        wxString hotkey_delete = "\u232b";
+    #else
+        wxString hotkey_delete = "Del";
+    #endif
+        wxMenuItem* item_select_all = append_menu_item(editMenu, wxID_ANY, _(L("&Select all")) + sep + GUI::shortkey_ctrl_prefix() + sep_space + "A", _(L("Selects all objects")),
             [this](wxCommandEvent&) { m_plater->select_all(); }, "");
         editMenu->AppendSeparator();
-        wxMenuItem* item_delete_sel = append_menu_item(editMenu, wxID_ANY, _(L("&Delete selected")) + "\tDel", _(L("Deletes the current selection")),
+        wxMenuItem* item_delete_sel = append_menu_item(editMenu, wxID_ANY, _(L("&Delete selected")) + sep + hotkey_delete, _(L("Deletes the current selection")),
             [this](wxCommandEvent&) { m_plater->remove_selected(); }, "");
-        wxMenuItem* item_delete_all = append_menu_item(editMenu, wxID_ANY, _(L("Delete &all")) + "\tCtrl+Del", _(L("Deletes all objects")),
+        wxMenuItem* item_delete_all = append_menu_item(editMenu, wxID_ANY, _(L("Delete &all")) + sep + GUI::shortkey_ctrl_prefix() + sep_space + hotkey_delete, _(L("Deletes all objects")),
             [this](wxCommandEvent&) { m_plater->reset(); }, "");
 
         Bind(wxEVT_UPDATE_UI, [this](wxUpdateUIEvent& evt) { evt.Enable(can_select()); }, item_select_all->GetId());
@@ -398,12 +402,6 @@ void MainFrame::init_menubar()
 
     // View menu
     wxMenu* viewMenu = nullptr;
-    wxString sep =
-#ifdef _MSC_VER
-        "\t";
-#else
-        " - ";
-#endif
     if (m_plater) {
         viewMenu = new wxMenu();
         // The camera control accelerators are captured by GLCanvas3D::on_char().
diff --git a/src/slic3r/GUI/Plater.cpp b/src/slic3r/GUI/Plater.cpp
index f9ad7a39a..e96e74492 100644
--- a/src/slic3r/GUI/Plater.cpp
+++ b/src/slic3r/GUI/Plater.cpp
@@ -3017,13 +3017,20 @@ void Plater::on_extruders_change(int num_extruders)
 void Plater::on_config_change(const DynamicPrintConfig &config)
 {
     bool update_scheduled = false;
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+    bool bed_shape_changed = false;
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
     for (auto opt_key : p->config->diff(config)) {
         p->config->set_key_value(opt_key, config.option(opt_key)->clone());
         if (opt_key == "printer_technology")
             this->set_printer_technology(config.opt_enum<PrinterTechnology>(opt_key));
         else if (opt_key == "bed_shape") {
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+            bed_shape_changed = true;
+#else
             if (p->view3D) p->view3D->set_bed_shape(p->config->option<ConfigOptionPoints>(opt_key)->values);
             if (p->preview) p->preview->set_bed_shape(p->config->option<ConfigOptionPoints>(opt_key)->values);
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
             update_scheduled = true;
         } 
         else if (boost::starts_with(opt_key, "wipe_tower") ||
@@ -3049,8 +3056,12 @@ void Plater::on_config_change(const DynamicPrintConfig &config)
         }
         else if (opt_key == "printer_model") {
             // update to force bed selection(for texturing)
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+            bed_shape_changed = true;
+#else
             if (p->view3D) p->view3D->set_bed_shape(p->config->option<ConfigOptionPoints>("bed_shape")->values);
             if (p->preview) p->preview->set_bed_shape(p->config->option<ConfigOptionPoints>("bed_shape")->values);
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
             update_scheduled = true;
         }
         else if (opt_key == "host_type" && this->p->printer_technology == ptSLA) {
@@ -3063,6 +3074,14 @@ void Plater::on_config_change(const DynamicPrintConfig &config)
         p->sidebar->show_send(prin_host_opt != nullptr && !prin_host_opt->value.empty());
     }
 
+#if ENABLE_REWORKED_BED_SHAPE_CHANGE
+    if (bed_shape_changed)
+    {
+        if (p->view3D) p->view3D->set_bed_shape(p->config->option<ConfigOptionPoints>("bed_shape")->values);
+        if (p->preview) p->preview->set_bed_shape(p->config->option<ConfigOptionPoints>("bed_shape")->values);
+    }
+#endif // ENABLE_REWORKED_BED_SHAPE_CHANGE
+
     if (update_scheduled) 
         update();
 
diff --git a/src/slic3r/GUI/Tab.cpp b/src/slic3r/GUI/Tab.cpp
index 06282cd24..69b3c5b30 100644
--- a/src/slic3r/GUI/Tab.cpp
+++ b/src/slic3r/GUI/Tab.cpp
@@ -497,13 +497,15 @@ void TabSLAMaterial::init_options_list()
 
 void Tab::get_sys_and_mod_flags(const std::string& opt_key, bool& sys_page, bool& modified_page)
 {
-	auto opt = m_options_list.find(opt_key);
+    auto opt = m_options_list.find(opt_key);
 	if (sys_page) sys_page = (opt->second & osSystemValue) != 0;
 	modified_page |= (opt->second & osInitValue) == 0;
 }
 
 void Tab::update_changed_tree_ui()
 {
+	if (m_options_list.empty())
+        return;
 	auto cur_item = m_treectrl->GetFirstVisibleItem();
     if (!cur_item || !m_treectrl->IsVisible(cur_item))
         return;
@@ -689,9 +691,9 @@ void Tab::update_visibility()
 	Thaw();
 
     // to update tree items color
-    wxTheApp->CallAfter([this]() {
+//    wxTheApp->CallAfter([this]() {
         update_changed_tree_ui();
-    });
+//     });
 }
 
 Field* Tab::get_field(const t_config_option_key& opt_key, int opt_index/* = -1*/) const