Size a Project's Mixed-Colour Metadata to the Filaments in the CLI

The mixed-colour metadata options are parallel per-slot arrays in the project
config. A project saved before they were sized per slot stores a single value
for the gradient ones, and one saved before they existed stores none. The GUI
sizes all seven to the filament count when it opens a project; the CLI kept
the stored arrays and exported one-element defaults for absent ones, so a
project it exported carried one-element arrays where the GUI writes one entry
per filament. Slicing is unaffected, every reader treats a missing entry as
not mixed / no gradient, but the GUI-vs-CLI comparison reported the four
gradient keys on every mixed-filament project.

The resize helper moves from PresetBundle.cpp, where it was file-local, to
PrintConfig.cpp next to set_filament_dev_options(). It creates an option the
config lacks before sizing it, a no-op for the bundle's project config where
all seven always exist. The CLI calls it with its filament count once the
project and loaded filaments are merged, after the check that every mixed
slot has a filament of its own.

.claude/skills/orca-profiles/references/extruder-variants.md

@@ -105,12 +105,11 @@ Rules:
    `single_extruder_multi_material` off, and in the app when the printer tab loads a printer with a
    different number of extruders, the pair is rebuilt from `extruder_variant_list` (one
    `Direct Drive Standard` per extruder when the list is absent) and the variant arrays are resized to
-   the rebuilt pair, padded with their first value or cut. The `machine_max_*` limits are padded the
-   same way, so extruder 2 and up of a list-less printer take extruder 1's normal limit as their
-   silent one too. The resize skips `hotend_heating_rate` / `hotend_cooling_rate`: they keep their
-   width, and an extruder beyond it reads their first value. With the three in agreement that changes
-   nothing; a pair written without the list is replaced. A listed variant the pair lacks is a menu
-   choice that reads variant index 0.
+   the rebuilt pair, padded with their first value or cut. The resize skips the `machine_max_*` limits
+   and `hotend_heating_rate` / `hotend_cooling_rate`: they keep their width, and an extruder beyond it
+   reads their first value, so extruder 2 and up of a list-less printer take extruder 1's normal limit
+   as their silent one too. With the three in agreement that changes nothing; a pair written without
+   the list is replaced. A listed variant the pair lacks is a menu choice that reads variant index 0.
    - The pair without `extruder_variant_list` slices, but the sidebar offers no variant switch and
      the app cannot add variants to a list-less process: nothing is lost while every extruder
      has exactly one variant, and every further variant is unreachable.

resources/web/guide/21/common.js

@@ -311,7 +311,7 @@ function CreatePrinterBlock(OneModel)
 
 	return	'<div class="PrinterBlock" onClick="ChooseModel(\''+vendor+'\',\''+OneModel['model']+'\')">'+
 			'	<div class="PImg">'+
-			'		<img class="ModelThumbnail" src="' + OneModel['cover'] + '" onerror="this.onerror=null;this.src=\'../img/printer-dummy.png\';"/>'+
+			'		<img class="ModelThumbnail" src="' + OneModel['cover'] + '" />'+
 			'	</div>'+
 			'	<div class="PrinterInfoMark">?</div>'+
 			'	<div class="PrinterInfo">'+

scripts/appimage_lib_policy.sh

@@ -23,13 +23,7 @@ appimage_is_host_library() {
 }
 
 appimage_is_elf_file() {
-    # Read the four-byte ELF magic rather than asking file(1): this runs once per candidate, and an
-    # AppDir holds thousands of them (the bundled Python runtime alone is ~5k files, none of them
-    # ELF). Two processes per call made this ~14 s of a ~95 s image build on its own.
-    local magic
-    [[ -f "$1" && -r "$1" ]] || return 1
-    IFS= read -r -n 4 -d '' magic < "$1" 2>/dev/null
-    [[ $magic == $'\177ELF' ]]
+    file -b "$1" 2>/dev/null | grep -q '^ELF '
 }
 
 appimage_list_direct_dependencies() {

src/OrcaSlicer.cpp

@@ -4094,6 +4094,8 @@ int CLI::run(int argc, char **argv)
             flush_and_exit(CLI_MIXED_FILAMENT_INVALID);
         }
     }
+    if (filament_count > 0)
+        resize_mixed_filament_metadata(m_print_config, size_t(filament_count), size_t(filament_count));
 
     m_print_config.option<ConfigOptionEnum<PrinterTechnology>>("printer_technology", true)->value = printer_technology;
 

src/dev-utils/platform/unix/build_linux_image.sh.in

@@ -118,13 +118,9 @@ bundle_dependency_closure() {
     # (scripts/check_appimage_libs.sh).
     local -a search_dirs=("$dst_dir")
 
-    # Walked with a read index rather than by reslicing the array: "${queue[@]:1}" rebuilds the whole
-    # queue on every pop, so draining it costs O(n^2). At the ~5k entries this bundle reaches that was
-    # ~22 s of the image build spent copying an array around.
-    local head=0
-    while [ "$head" -lt ${#queue[@]} ]; do
-        target="${queue[$head]}"
-        head=$((head + 1))
+    while [ ${#queue[@]} -gt 0 ]; do
+        target="${queue[0]}"
+        queue=("${queue[@]:1}")
 
         if [ ! -e "$target" ] || ! appimage_is_elf_file "$target"; then
             continue

src/libslic3r/PresetBundle.cpp

@@ -3601,24 +3601,6 @@ void PresetBundle::export_selections(AppConfig &config)
     BOOST_LOG_TRIVIAL(info) << __FUNCTION__ << boost::format(": printer %1%, print %2%, filaments[0] %3% ")%printers.get_selected_preset_name() % prints.get_selected_preset_name() %filament_presets[0];
 }
 
-// Preserve metadata only for existing colour slots; new slots get false/empty defaults.
-static void resize_mixed_filament_metadata(DynamicPrintConfig &config, size_t old_slot_count, size_t new_slot_count)
-{
-    auto resize = [old_slot_count, new_slot_count](auto *opt) {
-        if (opt) {
-            opt->values.resize(std::min(old_slot_count, opt->values.size()));
-            opt->values.resize(new_slot_count);
-        }
-    };
-    resize(config.option<ConfigOptionBools>("filament_is_mixed"));
-    resize(config.option<ConfigOptionStrings>("filament_mixed_components"));
-    resize(config.option<ConfigOptionStrings>("filament_mixed_sublayer_ratios"));
-    resize(config.option<ConfigOptionBools>("filament_mixed_gradient"));
-    resize(config.option<ConfigOptionStrings>("filament_mixed_gradient_range"));
-    resize(config.option<ConfigOptionStrings>("filament_mixed_gradient_curve"));
-    resize(config.option<ConfigOptionBools>("filament_mixed_gradient_per_part"));
-}
-
 void PresetBundle::set_num_filaments(unsigned int n, std::string new_color)
 {
     unsigned old_filament_count = this->filament_presets.size();

src/libslic3r/PrintConfig.cpp

@@ -10030,13 +10030,6 @@ static void extend_extruder_variant(DynamicPrintConfig& config, const unsigned i
             printer_extruder_variant_opt->values.insert(printer_extruder_variant_opt->values.end(), variants_list.begin(), variants_list.end());
         }
     }
-
-    // 3. Size the machine limits to the rebuilt variants, padded with their first value like the other variant keys.
-    // They are not extruder option keys, so the resize loop in set_num_extruders skips them.
-    const auto &defaults = FullPrintConfig::defaults();
-    for (const std::string &key : printer_options_with_variant_2)
-        if (auto *opt = config.option<ConfigOptionFloats>(key))
-            opt->resize(config.get_parameter_size(key, num_extruders), defaults.option(key));
 }
 
 void DynamicPrintConfig::set_num_extruders(unsigned int num_extruders)
@@ -10845,6 +10838,21 @@ void set_filament_dev_options(DynamicPrintConfig &config, const std::vector<cons
     }
 }
 
+void resize_mixed_filament_metadata(DynamicPrintConfig &config, size_t old_slot_count, size_t new_slot_count)
+{
+    auto resize = [old_slot_count, new_slot_count](auto *opt) {
+        opt->values.resize(std::min(old_slot_count, opt->values.size()));
+        opt->values.resize(new_slot_count);
+    };
+    resize(config.option<ConfigOptionBools>("filament_is_mixed", true));
+    resize(config.option<ConfigOptionStrings>("filament_mixed_components", true));
+    resize(config.option<ConfigOptionStrings>("filament_mixed_sublayer_ratios", true));
+    resize(config.option<ConfigOptionBools>("filament_mixed_gradient", true));
+    resize(config.option<ConfigOptionStrings>("filament_mixed_gradient_range", true));
+    resize(config.option<ConfigOptionStrings>("filament_mixed_gradient_curve", true));
+    resize(config.option<ConfigOptionBools>("filament_mixed_gradient_per_part", true));
+}
+
 
 //used for object/region config
 //use the smallest of multiple to single

src/libslic3r/PrintConfig.hpp

@@ -933,6 +933,10 @@ extern std::set<std::string> filament_dev_options;
 // filament_configs, one config per filament in slot order, as the filaments' values one after another.
 void set_filament_dev_options(DynamicPrintConfig &config, const std::vector<const DynamicPrintConfig *> &filament_configs);
 
+// Orca: sizes the per-slot mixed-colour metadata options to new_slot_count, keeping the first
+// old_slot_count values; an option the config lacks is created.
+void resize_mixed_filament_metadata(DynamicPrintConfig &config, size_t old_slot_count, size_t new_slot_count);
+
 extern void update_static_print_config_from_dynamic(ConfigBase& config, const DynamicPrintConfig& dest_config, std::vector<int> variant_index, std::set<std::string>& key_set1, int stride = 1);
 extern void compute_filament_override_value(const std::string& opt_key, const ConfigOption *opt_old_machine, const ConfigOption *opt_new_machine, const ConfigOption *opt_new_filament, const DynamicPrintConfig& new_full_config,
     t_config_option_keys& diff_keys, DynamicPrintConfig& filament_overrides, std::vector<int>& f_map_indices);

src/slic3r/GUI/PublishSettingsDialog.cpp

@@ -14,7 +14,6 @@
 #include "Widgets/DialogButtons.hpp"
 #include "Widgets/StaticLine.hpp"
 #include "Widgets/StateColor.hpp"
-#include "Widgets/SwitchButton.hpp"
 
 #include "libslic3r/PrintConfig.hpp"
 #include "libslic3r/Preset.hpp"
@@ -865,25 +864,34 @@ void PublishSettingsDialog::build_option_model()
     };
 
     // --- Phase 1: printer per-extruder retraction settings (first, mirroring the sidebar's
-    // Printer group), from the printer tab's "Extruder" page. One inner tab per extruder (named
-    // as on the printer tab's switch, e.g. "Left Extruder"/"Right Extruder" via
-    // Tab::translate_category), each holding that extruder's Retraction and Z-Hop rows with
-    // per-extruder "#N" values.
+    // Printer group), from the printer tab's "Extruder"/"Extruder N" pages. One inner tab per
+    // extruder (e.g. "Left Extruder"/"Right Extruder" via Tab::translate_category), each holding
+    // that extruder's Retraction and Z-Hop rows with per-extruder "#N" values.
     {
         size_t g = section_group_for(Section::Printer);
         std::set<std::string> printer_added;
         for (Tab* tab : wxGetApp().tabs_list) {
-            // The page's controls edit the extruder chosen on the printer tab's switch, so its
-            // option list is read once per extruder.
-            auto*       printer_tab = dynamic_cast<TabPrinter*>(tab);
-            const Page* page        = printer_tab ? printer_tab->extruder_page() : nullptr;
-            if (page == nullptr)
+            if (tab->m_type != Preset::TYPE_PRINTER)
                 continue;
-            const size_t extruders_count = printer_tab->m_extruders_count;
-            for (size_t extruder_idx = 0; extruder_idx < extruders_count; ++extruder_idx) {
-                const wxString page_title = Tab::translate_category(extruders_count > 1 ? wxString::Format("Extruder %d", int(extruder_idx + 1)) : wxString("Extruder"), tab->m_type);
-                // Retraction and Z-Hop values are stored per variant column, not per extruder.
-                const int variant_index = printer_tab->extruder_variant_index(int(extruder_idx));
+            for (const PageShp& page : tab->m_pages) {
+                if (!page->title().StartsWith("Extruder"))
+                    continue;
+                // The extruder index of this page: its options are appended with the same
+                // "#N" opt_index (opt.second.second), so derive the tab's index from the first
+                // allowlisted option; skip the page when none is found (defensive).
+                int extruder_idx = -1;
+                for (const ConfigOptionsGroupShp& optgroup : page->m_optgroups) {
+                    if (optgroup->title != "Retraction" && optgroup->title != "Z-Hop")
+                        continue;
+                    for (const auto& opt : optgroup->opt_map())
+                        if (extruder_idx < 0)
+                            extruder_idx = opt.second.second;
+                    if (extruder_idx >= 0)
+                        break;
+                }
+                if (extruder_idx < 0)
+                    continue;
+                const wxString page_title = Tab::translate_category(page->title(), tab->m_type);
                 for (const ConfigOptionsGroupShp& optgroup : page->m_optgroups) {
                     // Allowlist on the untranslated optgroup title; the "Retraction when
                     // switching material" group is intentionally skipped.
@@ -891,17 +899,17 @@ void PublishSettingsDialog::build_option_model()
                         continue;
                     const wxString subcategory = _(optgroup->title);
                     for (const auto& opt : optgroup->opt_map()) {
+                        const std::string& opt_id   = opt.first;
                         const std::string& pure_key = opt.second.first;
                         // Rows are keyed by the full per-extruder "#N" opt_id so each extruder
                         // tab publishes its own value; GetPublishedKeys() emits the checked rows
                         // as-is.
-                        const std::string opt_id = pure_key + "#" + std::to_string(variant_index);
                         if (!printer_added.insert(opt_id).second)
                             continue;
                         wxString label, value, unit;
                         if (!option_text(opt_id, pure_key, label, value, unit))
                             continue;
-                        size_t cat_index = category_index_for(page_title, Section::Printer, g, extruder_idx);
+                        size_t cat_index = category_index_for(page_title, Section::Printer, g, size_t(extruder_idx));
                         size_t sub_index = subcategory_index_for(cat_index, subcategory, optgroup->icon);
                         add_row_ui(opt_id, label, value, unit, cat_index, sub_index);
                     }
@@ -1090,10 +1098,6 @@ void PublishSettingsDialog::build_option_model()
     for (SectionGroup& section : m_sections)
         if (!section.categories.empty())
             section.tabs->SelectItem(0);
-    // Orca: the Printer section shows its extruders on the same switch as the printer tab's Extruder page.
-    for (size_t s = 0; s < m_sections.size(); ++s)
-        if (m_sections[s].kind == Section::Printer && m_sections[s].categories.size() > 1)
-            setup_variant_switch(s);
     if (!m_sections.empty()) {
         m_outer_tabs->SelectItem(0);
         show_outer_page(0);
@@ -1626,8 +1630,6 @@ void PublishSettingsDialog::show_inner_page(size_t section_index, int inner_inde
         section.selected_mixed = -1;
     }
     section.selected_inner = inner_index;
-    if (section.variant_switch != nullptr)
-        section.variant_switch->SetSelection(inner_index); // fires its event, which ignores the shown page
     Category& category     = m_categories[section.categories[inner_index]];
     category.page->Show();
     category.scroll->FitInside();
@@ -1637,32 +1639,6 @@ void PublishSettingsDialog::show_inner_page(size_t section_index, int inner_inde
     section.page_host_sizer->Layout();
 }
 
-void PublishSettingsDialog::setup_variant_switch(size_t section_index)
-{
-    SectionGroup& section = m_sections[section_index];
-    std::vector<wxString> titles;
-    for (size_t category : section.categories)
-        titles.push_back(m_categories[category].title);
-
-    section.variant_switch = new MultiSwitchButton(section.page);
-    section.variant_switch->SetFitToOptions();
-    section.variant_switch->SetOptions(titles);
-    section.variant_switch->SetSelection(section.selected_inner);
-    section.variant_switch->Bind(wxCUSTOMEVT_MULTISWITCH_SELECTION, [this, section_index](wxCommandEvent& evt) {
-        evt.Skip();
-        // The hidden tab strip stays the selection model; its event shows the page.
-        SectionGroup& sec = m_sections[section_index];
-        if (evt.GetInt() != sec.selected_inner)
-            sec.tabs->SelectItem(evt.GetInt());
-    });
-
-    // The switch takes the place of the tab strip, centered like on the printer tab.
-    wxSizer* page_sizer = section.page->GetSizer();
-    page_sizer->Insert(1, section.variant_switch, 0, wxALIGN_CENTER_HORIZONTAL | wxTOP, FromDIP(4));
-    section.tabs->Hide();
-    section.page->Layout();
-}
-
 void PublishSettingsDialog::show_mixed_page(size_t section_index, int mixed_index)
 {
     if (section_index >= m_sections.size())
@@ -2208,13 +2184,6 @@ void PublishSettingsDialog::refresh_tab_indicators()
         for (size_t i = 0; i < section.categories.size(); ++i) {
             const bool on = category_has_selection(m_categories[section.categories[i]]);
             section.tabs->SetItemIndicator(static_cast<unsigned int>(i), on);
-            // The switch has no indicator dot; mark its option text instead.
-            if (section.variant_switch != nullptr) {
-                const wxString& title = m_categories[section.categories[i]].title;
-                const wxString  text  = on ? title + wxString(" ") + wxString(wxUniChar(0x2022)) : title;
-                if (section.variant_switch->GetOptionText(static_cast<unsigned int>(i)) != text)
-                    section.variant_switch->SetOptionText(static_cast<unsigned int>(i), text);
-            }
             any = any || on;
         }
         if (section.mixed_tabs != nullptr)
@@ -2279,8 +2248,6 @@ void PublishSettingsDialog::on_dpi_changed(const wxRect& suggested_rect)
         section.tabs->Rescale();
         if (section.mixed_tabs != nullptr)
             section.mixed_tabs->Rescale();
-        if (section.variant_switch != nullptr)
-            section.variant_switch->Rescale();
     }
 
     // Refresh the per-row Color chips at the new DPI (they carry the slot number too).

src/slic3r/GUI/PublishSettingsDialog.hpp

@@ -37,7 +37,6 @@ namespace Slic3r { class DynamicPrintConfig; }
 class TextInput;
 class StaticLine;
 class CheckBox;
-class MultiSwitchButton;
 
 namespace Slic3r { namespace GUI {
 
@@ -196,10 +195,6 @@ private:
         ScalableBitmap icon_bmp;      // tab icon next to the title; rescaled on DPI change
         wxPanel* page{nullptr};
         TabCtrl* tabs{nullptr};
-        // Printer section with several extruders: the extruder switch shown instead of `tabs`, the
-        // same MultiSwitchButton (and option names) as the printer tab's Extruder page. One option
-        // per entry of `categories`, named by its title; `tabs` stays as the hidden selection model.
-        MultiSwitchButton* variant_switch{nullptr};
         // Second tab strip, below the main one, listing only the mixed-color filament slots.
         // Present on the Material section only (null elsewhere).
         TabCtrl* mixed_tabs{nullptr};
@@ -282,8 +277,6 @@ private:
     bool row_is_visible(const Row& row) const;
     void apply_visibility();
     void bind_tab_events();
-    // Replaces a section's inner tab strip with a variant switch (see SectionGroup::variant_switch).
-    void setup_variant_switch(size_t section_index);
 
     TabCtrl* m_outer_tabs{nullptr};
     wxPanel* m_outer_host{nullptr};

src/slic3r/GUI/Tab.cpp

@@ -811,12 +811,6 @@ wxString Tab::translate_category(const wxString& title, Preset::Type preset_type
         }
         return _("Extruder") + title.SubString(8, title.Last());
     }
-    // Orca: one "Extruder" page serves all extruders; name it "Extruders" when there are several.
-    if (preset_type == Preset::TYPE_PRINTER && title == "Extruder") {
-        auto preset = wxGetApp().preset_bundle;
-        if (preset && preset->get_printer_extruder_count() > 1)
-            return _("Extruders");
-    }
     return _(title);
 }
 
@@ -1159,38 +1153,6 @@ std::string Tab::options_list_storage_key(const std::string& opt_key) const
     return (serialized || is_plugin_field) ? opt_key : opt_key + "#0";
 }
 
-// Orca: deep_diff() flags every vector entry at or past the reference vector's length as changed,
-// whatever its value (e.g. the values of an extruder added by raising the extruder count). A vector
-// grows by copying its first entry (ConfigOptionVector::resize), so such an entry only counts as
-// changed when it differs from the reference's first entry, as before Orca's deep_diff() change.
-// The change of the count itself shows on "extruders_count".
-static void drop_unchanged_added_entries(std::vector<std::string> &options, const DynamicPrintConfig &current, const Preset *reference)
-{
-    if (reference == nullptr)
-        return;
-    // deep_diff() lists a key's entries one after another, so serialize each key's vectors once.
-    std::string              serialized_key;
-    std::vector<std::string> cur_values;
-    std::string              ref_first;
-    options.erase(std::remove_if(options.begin(), options.end(), [&](const std::string &opt) {
-        const auto pos = opt.find('#');
-        if (pos == std::string::npos)
-            return false;
-        const std::string key = opt.substr(0, pos);
-        const size_t      idx = size_t(std::atoi(opt.c_str() + pos + 1));
-        auto ref = dynamic_cast<const ConfigOptionVectorBase *>(reference->config.option(key));
-        auto cur = dynamic_cast<const ConfigOptionVectorBase *>(current.option(key));
-        if (ref == nullptr || cur == nullptr || idx < ref->size() || ref->size() == 0 || idx >= cur->size())
-            return false;
-        if (key != serialized_key) {
-            serialized_key = key;
-            cur_values     = cur->vserialize();
-            ref_first      = ref->vserialize().front();
-        }
-        return cur_values[idx] == ref_first;
-    }), options.end());
-}
-
 void Tab::update_all_extruder_options_status()
 {
     if (!m_extruder_switch && !m_variant_combo) {
@@ -1221,8 +1183,6 @@ void Tab::update_all_extruder_options_status()
 
     auto dirty_options = m_presets->current_dirty_options(true);
     auto nonsys_options = m_presets->current_different_from_parent_options(true);
-    if (m_type == Preset::TYPE_PRINTER)
-        update_custom_dirty(dirty_options, nonsys_options);
     auto filter_extruder_options = [](const std::vector<std::string>& options) {
         std::vector<std::string> filtered_options;
         for (const auto& opt : options) {
@@ -1271,7 +1231,7 @@ void Tab::update_extruder_switch_colors()
 
         if (m_active_page) {
             if (m_active_page->title() == "Speed" || m_active_page->title() == "Motion ability" || m_active_page->title() == "Filament" ||
-                m_active_page->title() == "Setting Overrides" || m_active_page->title() == "Multimaterial" || is_printer_extruder_page(m_active_page)) {
+                m_active_page->title() == "Setting Overrides" || m_active_page->title() == "Multimaterial") {
                 for (auto page_ptr : m_pages) {
                     if (page_ptr.get() == m_active_page) {
                         pages_to_check.push_back(page_ptr);
@@ -1302,8 +1262,8 @@ void Tab::update_extruder_switch_colors()
 void Tab::check_extruder_options_status(int index, bool &sys_extruder, bool &modified_extruder, const std::vector<PageShp>& pages_to_check)
 {
     int config_index = index;
-    int extruder_id  = index;
     if (m_type == Preset::TYPE_PRINT || m_type == Preset::TYPE_PRINTER || m_type == Preset::TYPE_MODEL) {
+        int extruder_id;
         NozzleVolumeType nozzle_type;
         parse_extruder_selection(index, extruder_id, nozzle_type);
 
@@ -1336,10 +1296,6 @@ void Tab::check_extruder_options_status(int index, bool &sys_extruder, bool &mod
                 }
 
                 std::string target_opt_key = base_opt_key + "#" + std::to_string(config_index * stride);
-                // Orca: on the printer's Extruder page only per-variant options use the variant column,
-                // the others (nozzle_diameter, extruder_offset, ...) are indexed by the extruder.
-                if (is_printer_extruder_page(page.get()) && printer_options_with_variant_1.count(base_opt_key) == 0)
-                    target_opt_key = base_opt_key + "#" + std::to_string(extruder_id);
 
                 auto status_iter = m_all_extruder_options_status.find(target_opt_key);
                 if (status_iter != m_all_extruder_options_status.end()) {
@@ -1380,6 +1336,18 @@ void TabPrinter::init_options_list()
     Tab::init_options_list();
     if (m_printer_technology == ptFFF)
         m_options_list.emplace("extruders_count", m_opt_status_value);
+    for (size_t i = 1; i < m_extruders_count; ++i) {
+        wxString target_title = wxString::Format("Extruder %d", int(i + 1));
+        for (auto &page : m_pages) {
+            if (page->title() == target_title) {
+                for (auto group : page->m_optgroups) {
+                    for (auto &opt : group->opt_map())
+                        m_options_list.emplace(opt.first, m_opt_status_value);
+                }
+                break;
+            }
+        }
+    }
 }
 
 void TabPrinter::msw_rescale()
@@ -1469,7 +1437,7 @@ void Tab::update_changed_tree_ui()
                     get_sys_and_mod_flags("compatible_printers", sys_page, modified_page);
                 }
             }
-            if (page->title() == "Speed" || page->title() == "Motion ability" || page->title() == "Filament" || page->title() == "Setting Overrides" || page->title() == "Multimaterial" || is_printer_extruder_page(page.get())) {
+            if (page->title() == "Speed" || page->title() == "Motion ability" || page->title() == "Filament" || page->title() == "Setting Overrides" || page->title() == "Multimaterial") {
                 auto options = generate_extruder_options();
                 for (size_t switch_index = 0; switch_index < options.size(); ++switch_index) {
                     std::vector<PageShp> pages_to_check = { page };
@@ -1572,10 +1540,6 @@ void Tab::on_roll_back_value(const bool to_sys /*= true*/)
 
     m_postpone_update_ui = false;
 
-    // Orca: the restored config may have another extruder count than the tab shows.
-    if (auto printer_tab = dynamic_cast<TabPrinter *>(this))
-        printer_tab->sync_extruders_count();
-
     // When all values are rolled, then we have to update whole tab in respect to the reverted values
     update();
     if (m_active_page)
@@ -1913,17 +1877,6 @@ static wxString pad_combo_value_for_config(const DynamicPrintConfig &config)
     return config.opt_bool("pad_enable") ? (config.opt_bool("pad_around_object") ? _("Around object") : _("Below object")) : _("None");
 }
 
-// Rebuilds the variant switch of every tab that has one, e.g. after the extruder count or a nozzle volume type changed.
-static void update_all_extruder_variants(int extruder_idx = -1)
-{
-    for (auto tab : wxGetApp().tabs_list)
-        tab->update_extruder_variants(extruder_idx);
-    if (auto tab = wxGetApp().plate_tab)
-        tab->update_extruder_variants(extruder_idx);
-    for (auto tab : wxGetApp().model_tabs_list)
-        tab->update_extruder_variants(extruder_idx);
-}
-
 void Tab::on_value_change(const std::string& opt_key, const boost::any& value)
 {
     // Orca:
@@ -2366,7 +2319,15 @@ void Tab::on_value_change(const std::string& opt_key, const boost::any& value)
 
     if (opt_key.find("nozzle_volume_type") != std::string::npos) {
         int extruder_idx = std::atoi(opt_key.substr(opt_key.find_last_of('#') + 1).c_str());
-        update_all_extruder_variants(extruder_idx);
+        for (auto tab : wxGetApp().tabs_list) {
+            tab->update_extruder_variants(extruder_idx);
+        }
+        if (auto tab = wxGetApp().plate_tab) {
+            tab->update_extruder_variants(extruder_idx);
+        }
+        for (auto tab : wxGetApp().model_tabs_list) {
+            tab->update_extruder_variants(extruder_idx);
+        }
         if (wxGetApp().app_config->get("auto_calculate_flush") == "all") {
             wxGetApp().plater()->sidebar().auto_calc_flushing_volumes(-1,extruder_idx);
         }
@@ -5724,13 +5685,9 @@ if (is_marlin_flavor)
             size_t extruders_count = size_t(boost::any_cast<int>(v));
             wxTheApp->CallAfter([this, opt_key, value, extruders_count]() {
                 if (opt_key == "extruders_count" || opt_key == "single_extruder_multi_material") {
-                    const size_t old_extruders_count = m_extruders_count;
                     extruders_count_changed(extruders_count);
                     init_options_list(); // m_options_list should be updated before UI updating
                     update_dirty();
-                    // Orca: the variant switches (here, Process in the sidebar, ...) list one option per extruder.
-                    if (m_extruders_count != old_extruders_count)
-                        update_all_extruder_variants();
                     if (opt_key == "single_extruder_multi_material") { // the single_extruder_multimaterial was added to force pages
                         on_value_change(opt_key, value);                      // rebuild - let's make sure the on_value_change is not skipped
 
@@ -5740,7 +5697,6 @@ if (is_marlin_flavor)
 // Orca: we use a different logic here. If SEMM is enabled, we set extruder count to 1.
 #if 1
                             extruders_count_changed(1);
-                            update_all_extruder_variants();
 #else
 
                             std::vector<double> nozzle_diameters =
@@ -5812,13 +5768,14 @@ if (is_marlin_flavor)
         m_pages.insert(m_pages.end() - n_after_single_extruder_MM, page);
     }
 
-    // Orca: a single "Extruder" page serves all extruders. Its controls are created once for extruder 0;
-    // switch_excluder() re-targets them to the extruder selected on the variant switch (m_extruder_switch),
-    // which the printer tab shows on this page too.
-    if (extruder_page() == nullptr && m_extruders_count > 0) {
-        const size_t extruder_idx = 0;
-        auto page = add_options_page(L("Extruder"), "custom-gcode_extruder", true); // ORCA: icon only visible on placeholders
-        m_pages.insert(m_pages.begin() + n_before_extruders, page);
+    // Orca: build missed extruder pages
+    for (auto extruder_idx = m_extruders_count_old; extruder_idx < m_extruders_count; ++extruder_idx) {
+        const wxString& page_name = (m_extruders_count > 1) ? wxString::Format("Extruder %d", int(extruder_idx + 1)) : wxString::Format("Extruder");
+
+        //# build page
+        //const wxString& page_name = wxString::Format("Extruder %d", int(extruder_idx + 1));
+        auto page = add_options_page(page_name, "custom-gcode_extruder", true); // ORCA: icon only visible on placeholders
+        m_pages.insert(m_pages.begin() + n_before_extruders + extruder_idx, page);
 
         auto optgroup = page->new_optgroup(L("Basic information"), L"param_information", -1, true);
             optgroup->append_single_option_line("nozzle_diameter", "printer_extruder_basic_information#nozzle-diameter", extruder_idx);
@@ -5831,10 +5788,8 @@ if (is_marlin_flavor)
             option.opt.full_width = true;
             optgroup->append_single_option_line(option, "printer_extruder_basic_information#extruder-offset-position");
 
-            optgroup->m_on_change = [this](const t_config_option_key& opt_key, boost::any value)
+            optgroup->m_on_change = [this, extruder_idx](const t_config_option_key& opt_key, boost::any value)
             {
-                // The page edits the extruder selected on the variant switch.
-                const size_t extruder_idx = size_t(get_current_active_extruder());
                 bool is_SEMM = m_config->opt_bool("single_extruder_multi_material");
                 if (is_SEMM && m_extruders_count > 1 && boost::starts_with(opt_key, "nozzle_diameter"))
                 {
@@ -5929,22 +5884,22 @@ if (is_marlin_flavor)
             //optgroup->append_line(line);
 #endif
     }
-
-    // The page holds only the "#0" controls, so register every extruder's options with the search
-    // index under "Extruder N"; a search hit selects that extruder (TabPrinter::activate_option()).
-    if (Page *page = extruder_page()) {
-        auto &index = wxGetApp().sidebar().settings_index();
-        for (auto &group : page->m_optgroups) {
-            group->set_config_category_and_type(page->title(), m_type);
-            for (auto &opt : group->opt_map()) {
-                if (opt.second.second < 0)
-                    continue;
-                for (size_t i = 0; i < m_extruders_count; ++i) {
-                    const wxString category = m_extruders_count > 1 ? wxString::Format("Extruder %d", int(i + 1)) : wxString("Extruder");
-                    index.add_key(opt.second.first + "#" + std::to_string(i), m_type, group->title, category, group->icon);
-                }
-            }
-        }
+    // BBS. No extra extruder page for single physical extruder machine
+    // # remove extra pages
+    auto &first_extruder_title = const_cast<wxString &>(m_pages[n_before_extruders]->title());
+    if (m_extruders_count < m_extruders_count_old) {
+        m_pages.erase(	m_pages.begin() + n_before_extruders + m_extruders_count,
+                        m_pages.begin() + n_before_extruders + m_extruders_count_old);
+        if (m_extruders_count == 1)
+            first_extruder_title = wxString::Format("Extruder");
+    } else if (m_extruders_count_old == 1) {
+        first_extruder_title = wxString::Format("Extruder %d", 1);
+    }
+    auto & index = wxGetApp().sidebar().settings_index();
+    for (auto &group : m_pages[n_before_extruders]->m_optgroups) {
+        group->set_config_category_and_type(first_extruder_title, m_type);
+        for (auto &opt : group->opt_map())
+            index.add_key(opt.first + "#0", m_type, group->title, first_extruder_title, group->icon);
     }
 
     Thaw();
@@ -6225,6 +6180,12 @@ void TabPrinter::toggle_options()
         return;
 
     auto nozzle_volumes = m_preset_bundle->project_config.option<ConfigOptionEnumsGeneric>("nozzle_volume_type");
+    auto extruders      = m_config->option<ConfigOptionEnumsGeneric>("extruder_type");
+        auto get_index_for_extruder =
+            [this, &extruders](int extruder_id, int stride = 1) {
+        return m_config->get_index_for_extruder(extruder_id + 1, "printer_extruder_id",
+            ExtruderType(extruders->values[extruder_id]), get_actual_nozzle_volume_type(extruder_id), "printer_extruder_variant", stride);
+    };
 
     //BBS: whether the preset is Bambu Lab printer
     bool is_BBL_printer = false;
@@ -6299,13 +6260,14 @@ void TabPrinter::toggle_options()
         toggle_option("tool_change_on_wipe_tower", !bSEMM && supports_wipe_tower_2 && extruders_count > 1);
         toggle_option("wait_for_temp_on_wipe_tower", !bSEMM && supports_wipe_tower_2 && extruders_count > 1);
     }
-    if (m_active_page->title() == L("Extruder") && m_extruders_count > 0)
+    wxString extruder_number;
+    long val = 1;
+    if ( m_active_page->title().IsSameAs(L("Extruder")) ||
+        (m_active_page->title().StartsWith("Extruder ", &extruder_number) && extruder_number.ToLong(&val) &&
+        val > 0 && (size_t)val <= m_extruders_count))
     {
-        // Orca: the single Extruder page edits the extruder selected on the variant switch; its
-        // controls carry field index 0 (i), the values are read for `extruder`.
-        const size_t i        = 0;
-        const size_t extruder = std::min<size_t>(size_t(get_current_active_extruder()), m_extruders_count - 1);
-        const int    variant_index = extruder_variant_index(int(extruder));
+        size_t i = size_t(val - 1);
+        int variant_index = get_index_for_extruder(i);
         bool have_retract_length = m_config->opt_float("retraction_length", variant_index) > 0;
 
         toggle_option("extruder_printable_area", false, i);          // disable
@@ -6332,7 +6294,7 @@ void TabPrinter::toggle_options()
         vec.resize(0);
         vec = {"retract_lift_above", "retract_lift_below", "retract_lift_enforce"};
         for (auto el : vec)
-          toggle_option(el, retraction && (m_config->opt_float("z_hop", variant_index) > 0), i);
+          toggle_option(el, retraction && (m_config->opt_float("z_hop", i) > 0), i);
 
         // some options only apply when not using firmware retraction
         vec.resize(0);
@@ -6385,7 +6347,7 @@ void TabPrinter::toggle_options()
         toggle_option("long_retractions_when_cut", !use_firmware_retraction && m_config->opt_int("enable_long_retraction_when_cut"), i);
         toggle_line("retraction_distances_when_cut", m_config->opt_bool("long_retractions_when_cut", variant_index), i);
 
-        toggle_option("travel_slope", m_config->opt_enum("z_hop_types", variant_index) != ZHopType::zhtNormal, i);
+        toggle_option("travel_slope", m_config->opt_enum("z_hop_types", i) != ZHopType::zhtNormal, i);
     }
 
     if (m_active_page->title() == L("Motion ability")) {
@@ -6459,16 +6421,12 @@ void TabPrinter::on_value_change(const std::string& opt_key, const boost::any& v
         return;
 
     const int pos = opt_key.find("#");
-    // Orca: fields of the single Extruder page keep index 0 but edit the selected extruder.
-    const int data_idx = pos > 0 ? extruder_page_data_index(opt_key) : -1;
 
     if (pos > 0) {
         std::string temp_str = opt_key;
         boost::erase_head(temp_str, pos + 1);
         int orig_opt_idx = static_cast<size_t>(atoi(temp_str.c_str()));
         int opt_idx = orig_opt_idx >= 0 ? orig_opt_idx : 0;
-        if (data_idx >= 0)
-            opt_idx = data_idx;
 
         std::string opt_key_pure = opt_key;
         boost::erase_tail(opt_key_pure, opt_key_pure.size() - pos);
@@ -6503,12 +6461,7 @@ void TabPrinter::on_value_change(const std::string& opt_key, const boost::any& v
         }
     }
 
-    // Orca: report Extruder page changes as "key#<extruder>", as the former "Extruder N" pages did,
-    // so per-extruder handling in Tab::on_value_change() sees the extruder that was edited.
-    if (data_idx >= 0)
-        Tab::on_value_change(opt_key.substr(0, pos) + "#" + std::to_string(get_current_active_extruder()), value);
-    else
-        Tab::on_value_change(opt_key, value);
+    Tab::on_value_change(opt_key, value);
 }
 
 void TabPrinter::update()
@@ -7440,7 +7393,12 @@ bool Tab::tree_sel_change_delayed(wxCommandEvent& event)
         // update_undo_buttons();
         this->OnActivate();
         m_parent->set_active_tab(this);
-        update_variant_sizer_visibility();
+        if (m_variant_sizer) {
+            wxWindow *variant_ctrl = m_extruder_switch ? (wxWindow *) m_extruder_switch : m_variant_combo;
+            m_main_sizer->Show(m_variant_sizer, variant_ctrl->IsThisEnabled() && !m_active_page->m_opt_id_map.empty() && !m_active_page->title().StartsWith("Extruder "));
+            if (m_extruder_sync) m_extruder_sync->Show(variant_ctrl->IsShown());
+            GetParent()->Layout();
+        }
 
         m_page_view->Thaw();
         return false;
@@ -7451,7 +7409,12 @@ bool Tab::tree_sel_change_delayed(wxCommandEvent& event)
         return false;
 
     m_active_page = page;
-    update_variant_sizer_visibility();
+    if (m_variant_sizer) {
+        wxWindow *variant_ctrl = m_extruder_switch ? (wxWindow *) m_extruder_switch : m_variant_combo;
+        m_main_sizer->Show(m_variant_sizer, variant_ctrl->IsThisEnabled() && !m_active_page->m_opt_id_map.empty() && !m_active_page->title().StartsWith("Extruder"));
+        if (m_extruder_sync) m_extruder_sync->Show(variant_ctrl->IsShown());
+        GetParent()->Layout();
+    }
 
     auto throw_if_canceled = std::function<void()>([this](){
 #ifdef WIN32
@@ -8277,11 +8240,9 @@ void Tab::update_extruder_variants(int extruder_id, bool reload)
         m_actual_nozzle_volumes.resize(extruder_nums, NozzleVolumeType::nvtStandard);
         for (int i = 0; i < extruder_nums; i++) m_actual_nozzle_volumes[i] = (NozzleVolumeType)nozzle_volumes->values[i];
 
-        // Orca: when every extruder uses the same variant (e.g. a non-Bambu dual-nozzle printer), the
-        // switch has no nozzle variants to select and nothing to sync. The printer tab still enables it
-        // to choose the extruder its Extruder and Motion ability pages edit.
-        m_extruder_switch_variants = extruder_nums >= 2 && m_preset_bundle->support_different_extruders();
-        if (m_extruder_switch_variants || (m_type == Preset::TYPE_PRINTER && extruder_nums >= 2)) {
+        // Orca: a non-Bambu dual-nozzle printer has two extruders but a single variant column, so
+        // the nozzle switch and sync button have nothing to act on. Only enable with real variants.
+        if (extruder_nums >= 2 && m_preset_bundle->support_different_extruders()) {
             auto options = generate_extruder_options();
             m_extruder_switch->SetOptions(options);
 
@@ -8320,8 +8281,12 @@ void Tab::update_extruder_variants(int extruder_id, bool reload)
     if (m_type == Preset::TYPE_PRINT) {
         update_pages_with_multi_variant();
     }
-    update_extruder_switch_colors();
-    update_variant_sizer_visibility();
+    if (m_variant_sizer) {
+        wxWindow *variant_ctrl = m_extruder_switch ? (wxWindow *) m_extruder_switch : m_variant_combo;
+        m_main_sizer->Show(m_variant_sizer, variant_ctrl->IsThisEnabled() && m_active_page && !m_active_page->m_opt_id_map.empty() && !m_active_page->title().StartsWith("Extruder "));
+        if (m_extruder_sync) m_extruder_sync->Show(variant_ctrl->IsShown());
+        GetParent()->Layout();
+    }
 }
 
 // The variant switch tags are the narrowest place a volume type is named, so they abbreviate it;
@@ -8396,21 +8361,12 @@ std::vector<wxString> Tab::generate_extruder_options()
         return options;
     }
 
-    // Orca: the printer tab has one tag per extruder, named as its former "Extruder N" pages were.
-    // parse_extruder_selection() counts a hybrid extruder as two tags; that still lines up because
-    // only the last extruder can be hybrid.
-    if (m_type == Preset::TYPE_PRINTER) {
-        for (int i = 0; i < extruder_nums; ++i)
-            options.push_back(translate_category(wxString::Format("Extruder %d", i + 1), m_type));
-        return options;
-    }
-
     std::string pt = m_preset_bundle->printers.get_edited_preset().get_printer_type(m_preset_bundle);
-    // Orca: the main/deputy toolhead names describe a Bambu dual-nozzle printer, where extruder 0 is
-    // the left (deputy) and extruder 1 the right (main) nozzle. Other printers number their tools.
-    const bool toolhead_names = extruder_nums == 2 && m_preset_bundle->is_bbl_vendor();
+    // Orca: the main/deputy toolhead names describe a dual-nozzle printer, where extruder 0 is the
+    // left (deputy) and extruder 1 the right (main) nozzle. From three extruders on the tools are
+    // interchangeable, so name them by index instead of repeating one side.
     for (int i = 0; i < extruder_nums; ++i) {
-        wxString extruder_name = !toolhead_names ? wxString::Format("T%d", i + 1) :
+        wxString extruder_name = extruder_nums > 2 ? wxString::Format("T%d", i + 1) :
                                                      _L(DevPrinterConfigUtil::get_toolhead_display_name(
                                                          pt, (i == 0) ? DEPUTY_EXTRUDER_ID : MAIN_EXTRUDER_ID,
                                                          ToolHeadComponent::Nozzle, ToolHeadNameCase::TitleCase, true));
@@ -8427,71 +8383,6 @@ std::vector<wxString> Tab::generate_extruder_options()
     return options;
 }
 
-Page *TabPrinter::extruder_page() const
-{
-    for (const PageShp &page : m_pages)
-        if (page->title() == "Extruder")
-            return page.get();
-    return nullptr;
-}
-
-int TabPrinter::extruder_page_data_index(const std::string &field_id) const
-{
-    if (Page *page = extruder_page())
-        for (const auto &group : page->m_optgroups)
-            if (auto it = group->opt_map().find(field_id); it != group->opt_map().end())
-                return it->second.second;
-    return -1;
-}
-
-int TabPrinter::extruder_variant_index(int extruder)
-{
-    const auto *extruders = m_config->option<ConfigOptionEnumsGeneric>("extruder_type");
-    const int   index     = extruder < int(extruders->size()) ?
-                                m_config->get_index_for_extruder(extruder + 1, "printer_extruder_id", ExtruderType(extruders->values[extruder]),
-                                                                 get_actual_nozzle_volume_type(extruder), "printer_extruder_variant") :
-                                -1;
-    return index < 0 ? extruder : index;
-}
-
-void TabPrinter::update_custom_dirty(std::vector<std::string> &dirty_options, std::vector<std::string> &nonsys_options)
-{
-    drop_unchanged_added_entries(dirty_options, *m_config, &m_presets->get_selected_preset());
-    drop_unchanged_added_entries(nonsys_options, *m_config, m_presets->get_selected_preset_parent());
-}
-
-void TabPrinter::sync_extruders_count()
-{
-    if (m_printer_technology != ptFFF)
-        return;
-    const auto *nozzle_diameter = m_config->option<ConfigOptionFloats>("nozzle_diameter");
-    if (nozzle_diameter == nullptr || nozzle_diameter->size() == m_extruders_count)
-        return;
-    extruders_count_changed(nozzle_diameter->size());
-    init_options_list();
-    update_all_extruder_variants();
-}
-
-void TabPrinter::activate_option(const std::string &opt_key, const wxString &category)
-{
-    wxString number;
-    long     n = 0;
-    const bool numbered = category.StartsWith("Extruder ", &number) && number.ToLong(&n);
-    if (extruder_page() == nullptr || (!numbered && category != "Extruder")) {
-        Tab::activate_option(opt_key, category);
-        return;
-    }
-
-    // Selecting fires the switch's event, which re-targets the page (switch_excluder()).
-    const int extruder_idx = (n >= 1 && n <= long(m_extruders_count)) ? int(n - 1) : 0;
-    if (m_extruder_switch && m_extruder_switch->IsThisEnabled() && extruder_idx != get_current_active_extruder())
-        m_extruder_switch->SetSelection(calculate_selection_index_for_extruder(extruder_idx, get_actual_nozzle_volume_type(extruder_idx)));
-
-    // The page's controls are created for index 0.
-    const auto pos = opt_key.find('#');
-    Tab::activate_option(pos == std::string::npos ? opt_key : opt_key.substr(0, pos) + "#0", "Extruder");
-}
-
 NozzleVolumeType Tab::get_actual_nozzle_volume_type(int extruder_id)
 {
     int extruder_count = m_preset_bundle->get_printer_extruder_count();
@@ -8568,44 +8459,18 @@ bool Tab::get_extruder_sync_enable_state(int extruder_id)
     return false;
 }
 
-bool Tab::variant_switch_active() const
-{
-    if (m_extruder_switch)
-        return m_extruder_switch->IsThisEnabled();
-    return m_variant_combo && m_variant_combo->IsThisEnabled();
-}
-
-void Tab::update_variant_sizer_visibility()
-{
-    if (!m_variant_sizer)
-        return;
-    const bool show = variant_switch_active() && m_active_page && !m_active_page->m_opt_id_map.empty();
-    m_main_sizer->Show(m_variant_sizer, show);
-    if (m_extruder_sync) {
-        m_extruder_sync->Show(show);
-        // Orca: copying between extruders is offered only between nozzle variants, and not on the Extruder page.
-        m_extruder_sync->Enable(m_extruder_switch_variants && !is_printer_extruder_page(m_active_page) &&
-                                get_extruder_sync_enable_state(get_current_active_extruder()));
-    }
-    GetParent()->Layout();
-}
-
 void Tab::switch_excluder(int extruder_id, bool reload)
 {
     Preset & printer_preset = m_preset_bundle->printers.get_edited_preset();
     auto nozzle_volumes = m_preset_bundle->project_config.option<ConfigOptionEnumsGeneric>("nozzle_volume_type");
     auto extruders      = printer_preset.config.option<ConfigOptionEnumsGeneric>("extruder_type");
 
-    // Orca: the printer tab re-targets its pages to the extruder selected on the switch. Resolved before
-    // the range check below, which keeps the extruder_type read in get_index_for_extruder in range.
-    if (m_type == Preset::TYPE_PRINTER && extruder_id == -1)
-        extruder_id = get_current_active_extruder();
     if (!m_variant_combo && (extruder_id >= (int)nozzle_volumes->size() || extruder_id >= (int)extruders->size()))
         extruder_id = 0;
     if (m_extruder_switch) {
         int current_extruder = get_current_active_extruder();
         bool sync_enable = get_extruder_sync_enable_state(current_extruder);
-        m_extruder_sync->Enable(m_extruder_switch_variants && sync_enable && !is_printer_extruder_page(m_active_page));
+        m_extruder_sync->Enable(m_extruder_switch->IsThisEnabled() && sync_enable);
         m_extruder_sync->Show();
         if (m_type != Preset::TYPE_PRINTER) {
             if (extruder_id == -1)
@@ -8632,26 +8497,24 @@ void Tab::switch_excluder(int extruder_id, bool reload)
         return;
     if (m_extruder_switch) m_extruder_switch->SetClientData(reinterpret_cast<void*>(static_cast<std::uintptr_t>(index)));
     if (m_variant_combo) m_variant_combo->SetClientData(reinterpret_cast<void *>(static_cast<std::uintptr_t>(index)));
+    wxWindow *variant_ctrl = m_extruder_switch ? (wxWindow *) m_extruder_switch : m_variant_combo;
     for (auto page : m_pages) {
         bool is_extruder = false;
-        int  page_index  = index;
         if (m_type == Preset::TYPE_PRINTER) {
-            if (page->title() == "Extruder")
+            if (page->title().StartsWith("Extruder")) {
+                int extruder_id2 = std::atoi(page->title().Mid(9).ToUTF8()) - 1;
+                if (extruder_id >= 0 && extruder_id2 != extruder_id)
+                    continue;
+                if (extruder_id2 > 0)
+                    index = get_index_for_extruder(extruder_id2);
                 is_extruder = true;
-            else if (page->title().StartsWith("Motion ability"))
-                page_index = get_index_for_extruder(extruder_id == -1 ? 0 : extruder_id, 2);
+            } else if (page->title().StartsWith("Motion ability")) {
+                index = get_index_for_extruder(extruder_id == -1 ? 0 : extruder_id, 2);
+            }
         }
         page->m_opt_id_map.clear();
         for (auto group : page->m_optgroups) {
             for (auto &opt : group->opt_map()) {
-                if (is_extruder && opt.second.second >= 0) {
-                    // Per-variant options use the variant column, the others (nozzle_diameter,
-                    // extruder_offset, ...) are sized by the extruder count and use the extruder.
-                    const int idx = printer_options_with_variant_1.count(opt.second.first) > 0 ? page_index : extruder_id;
-                    const_cast<int &>(opt.second.second) = idx;
-                    page->m_opt_id_map.insert({opt.second.first + "#" + std::to_string(idx), opt.first});
-                    continue;
-                }
                 auto iter = std::find(printer_extruder_options.begin(), printer_extruder_options.end(), opt.second.first);
                 if (iter != printer_extruder_options.end()) {
                     page->m_opt_id_map.insert({opt.first, opt.first});
@@ -8659,9 +8522,9 @@ void Tab::switch_excluder(int extruder_id, bool reload)
                 }
 
                 if (opt.second.second >= 0) {
-                    const_cast<int &>(opt.second.second) = page_index;
-                    page->m_opt_id_map.insert({opt.second.first + "#" + std::to_string(page_index), opt.first});
-                    group->draw_multi_extruder = variant_switch_active();
+                    const_cast<int &>(opt.second.second) = index;
+                    page->m_opt_id_map.insert({opt.second.first + "#" + std::to_string(index), opt.first});
+                    group->draw_multi_extruder = !is_extruder && variant_ctrl->IsThisEnabled();
                 }
             }
         }

src/slic3r/GUI/Tab.hpp

@@ -331,10 +331,6 @@ public:
     MultiSwitchButton *  m_variant_combo   = nullptr;
     ScalableButton *m_extruder_sync   = nullptr;
 	wxPanel *       m_extruder_sync_box  = nullptr;
-    // Orca: whether m_extruder_switch switches nozzle variants (it then offers sync between them).
-    // The printer tab also enables the switch for printers without variants, to choose the extruder
-    // its Extruder and Motion ability pages edit.
-    bool            m_extruder_switch_variants = false;
     std::vector<NozzleVolumeType> m_actual_nozzle_volumes;
 
 public:
@@ -391,13 +387,6 @@ public:
     void        update_changed_tree_ui();
 	void		update_undo_buttons();
     void        update_extruder_switch_colors();
-    // Whether the variant switch (m_extruder_switch / m_variant_combo) is enabled: on the printer tab for
-    // any multi-extruder printer, on the other tabs when it switches nozzle variants.
-    bool        variant_switch_active() const;
-    // Orca: whether `page` is the printer tab's single "Extruder" page, which edits the extruder selected on the switch.
-    bool        is_printer_extruder_page(const Page* page) const { return m_type == Preset::TYPE_PRINTER && page && page->title() == "Extruder"; }
-    // Shows the variant switch row on pages with options that follow it.
-    void        update_variant_sizer_visibility();
     void        update_all_extruder_options_status();
     void        check_extruder_options_status(int index, bool &sys_extruder, bool &modified_extruder, const std::vector<PageShp>& pages_to_check);
 
@@ -455,7 +444,7 @@ public:
 	virtual void    on_value_change(const std::string& opt_key, const boost::any& value);
 
     void            update_wiping_button_visibility();
-	virtual void	activate_option(const std::string& opt_key, const wxString& category);
+	void			activate_option(const std::string& opt_key, const wxString& category);
     void			apply_searcher();
 	void			cache_config_diff(const std::vector<std::string>& selected_options, const DynamicPrintConfig* config = nullptr);
 	void			apply_config_from_cache();
@@ -721,25 +710,6 @@ public:
 	void		cache_extruder_cnt(const DynamicPrintConfig* config = nullptr);
 	bool		apply_extruder_cnt_from_cache();
 	void		refresh_printer_agent_dropdown() const;
-
-	// Orca: a single "Extruder" page for all extruders. Its controls are created once (index 0) and
-	// switch_excluder() re-targets them to the extruder selected on m_extruder_switch.
-	Page*		extruder_page() const;
-	// Config index an "Extruder" page field (e.g. "retraction_length#0") currently edits, -1 if not on that page.
-	int			extruder_page_data_index(const std::string& field_id) const;
-	// Config index of an extruder's per-variant options (Retraction, Z-Hop, ...): its variant column
-	// for the nozzle selected on the switch, or the extruder index on a printer without variants.
-	int			extruder_variant_index(int extruder);
-	// After the config was restored (roll back): follow its extruder count, if it differs.
-	void		sync_extruders_count();
-	// Search jump to "Extruder N" / "key#N": selects extruder N on the switch, then activates the
-	// page's own field on the "Extruder" page.
-	void		activate_option(const std::string& opt_key, const wxString& category) override;
-
-protected:
-	// Orca: values of extruders added by raising the extruder count have no saved / system value to
-	// revert to; the change is shown on "extruders_count", not on each of their parameters.
-	void		update_custom_dirty(std::vector<std::string> &dirty_options, std::vector<std::string> &nonsys_options) override;
 };
 
 class TabSLAMaterial : public Tab

src/slic3r/plugin/host/PluginHostUi.cpp

@@ -28,7 +28,6 @@
 #include <wx/app.h>
 #include <wx/defs.h>
 #include <wx/thread.h>
-#include <wx/timer.h>
 #include <wx/toplevel.h>
 #include <wx/event.h>
 #include <wx/progdlg.h>
@@ -416,44 +415,6 @@ struct UiDockPanelHandle
     int id{0};
 };
 
-// Polls until the plater is shown on screen, then runs the callback with it (null when the app
-// is closing instead) and deletes itself. A plugin loaded at startup opens its panes from
-// on_load, before the main window exists, and a pane added before that window is laid out is
-// sized against the unsized frame and keeps that width (AuiMgr::track_docked_size).
-class PlaterShownWaiter : public wxTimer
-{
-public:
-    explicit PlaterShownWaiter(std::function<void(GUI::Plater*)> fn) : m_fn(std::move(fn)) {}
-
-    // True once the callback ran.
-    bool try_run()
-    {
-        const bool   closing = GUI::wxGetApp().is_closing();
-        GUI::Plater* plater  = closing ? nullptr : GUI::wxGetApp().plater();
-        if (!closing && (plater == nullptr || !plater->IsShownOnScreen()))
-            return false;
-        Stop();
-        m_fn(plater);
-        // Off the timer callback's stack: wxGTK's timeout callback still reads the timer after Notify().
-        GUI::wxGetApp().CallAfter([this]() { delete this; });
-        return true;
-    }
-
-    void Notify() override { try_run(); }
-
-private:
-    std::function<void(GUI::Plater*)> m_fn;
-};
-
-void run_when_plater_shown(std::function<void(GUI::Plater*)> fn)
-{
-    GUI::wxGetApp().CallAfter([fn = std::move(fn)]() mutable {
-        auto* waiter = new PlaterShownWaiter(std::move(fn));
-        if (!waiter->try_run())
-            waiter->Start(100);
-    });
-}
-
 py::object ui_create_dock_panel(const std::string& html, const std::string& title, int width, int height,
                                 py::object on_message, py::object on_close, const std::string& dock)
 {
@@ -473,13 +434,14 @@ py::object ui_create_dock_panel(const std::string& html, const std::string& titl
     const int new_id = UiRegistry::instance().reserve_id();
     UiRegistry::instance().bind(new_id, nullptr, plugin_key);
 
-    run_when_plater_shown([new_id, plugin_key, html, title, dock, w, h,
-                           msg_adapter = std::move(msg_adapter),
-                           close_holder = std::move(close_holder)](GUI::Plater* plater) mutable {
+    GUI::wxGetApp().CallAfter([new_id, plugin_key, html, title, dock, w, h,
+                               msg_adapter = std::move(msg_adapter),
+                               close_holder = std::move(close_holder)]() mutable {
         if (!UiRegistry::instance().is_open(new_id))
             return;
 
-        if (plater == nullptr) {
+        GUI::Plater* plater = GUI::wxGetApp().plater();
+        if (plater == nullptr || GUI::wxGetApp().is_closing()) {
             UiRegistry::instance().remove(new_id);
             return;
         }

tests/libslic3r/test_config_variant_expansion.cpp

@@ -800,43 +800,6 @@ TEST_CASE("A per-variant filament option read with a single value gives it to ev
     REQUIRE(config.option<ConfigOptionFloats>("pressure_advance")->values == std::vector<double>({0.021, 0.021, 0.021}));
 }
 
-// Machine limits (printer_options_with_variant_2) hold a (normal, silent) pair per printer variant, so the
-// printer Tab's Motion ability page can edit each extruder's own limits.
-TEST_CASE("set_num_extruders gives every printer variant its own pair of machine limits", "[Config]")
-{
-    DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
-    auto speed_x = [&config]() { return config.option<ConfigOptionFloats>("machine_max_speed_x")->values; };
-
-    SECTION("a new extruder's pair is padded with the first value, like the other variant keys") {
-        config.option<ConfigOptionFloats>("machine_max_speed_x")->values = {500., 200.};
-        config.set_num_extruders(3);
-        REQUIRE(config.option<ConfigOptionStrings>("printer_extruder_variant")->size() == 3);
-        REQUIRE(speed_x() == std::vector<double>({500., 200., 500., 500., 500., 500.}));
-    }
-
-    SECTION("per-extruder pairs are kept, and removing an extruder removes its pair") {
-        config.option<ConfigOptionFloats>("machine_max_speed_x")->values = {500., 200., 400., 150., 300., 100.};
-        config.set_num_extruders(3);
-        REQUIRE(speed_x() == std::vector<double>({500., 200., 400., 150., 300., 100.}));
-        config.set_num_extruders(2);
-        REQUIRE(speed_x() == std::vector<double>({500., 200., 400., 150.}));
-    }
-
-    SECTION("a printer with nozzle variants gets a pair per variant") {
-        // 2 extruders x 2 variants each = 4 variants
-        config.option<ConfigOptionStrings>("extruder_variant_list", true)->values = {"Direct Drive Standard,Direct Drive High Flow",
-                                                                                     "Direct Drive Standard,Direct Drive High Flow"};
-        const std::vector<double> per_variant = {500., 200., 510., 210., 520., 220., 530., 230.};
-        config.option<ConfigOptionFloats>("machine_max_speed_x")->values = per_variant;
-        config.set_num_extruders(2);
-        REQUIRE(speed_x() == per_variant);
-
-        config.option<ConfigOptionFloats>("machine_max_speed_x")->values = {500., 200.};
-        config.set_num_extruders(2);
-        REQUIRE(speed_x() == std::vector<double>({500., 200., 500., 500., 500., 500., 500., 500.}));
-    }
-}
-
 // The device drying options hold several values per filament, as many as each filament preset gives.
 TEST_CASE("The device drying options are rebuilt as each filament's values in slot order", "[Config]")
 {
@@ -863,3 +826,23 @@ TEST_CASE("The device drying options are rebuilt as each filament's values in sl
     set_filament_dev_options(config, {&two_values, &no_value});
     REQUIRE(config.option<ConfigOptionStrings>("filament_dev_ams_drying_ams_limitations")->values == std::vector<std::string>({"1", "0", ""}));
 }
+
+TEST_CASE("The mixed filament metadata is sized to the filament count", "[Config]")
+{
+    DynamicPrintConfig config;
+    config.option<ConfigOptionBools>("filament_is_mixed", true)->values            = {false, false, true};
+    config.option<ConfigOptionStrings>("filament_mixed_components", true)->values  = {"", "", "1,2"};
+    config.option<ConfigOptionBools>("filament_mixed_gradient", true)->values      = {false};
+    config.option<ConfigOptionStrings>("filament_mixed_gradient_range", true)->values = {""};
+
+    resize_mixed_filament_metadata(config, 3, 3);
+    REQUIRE(config.option<ConfigOptionBools>("filament_is_mixed")->values == std::vector<unsigned char>({false, false, true}));
+    REQUIRE(config.option<ConfigOptionStrings>("filament_mixed_components")->values == std::vector<std::string>({"", "", "1,2"}));
+    REQUIRE(config.option<ConfigOptionBools>("filament_mixed_gradient")->values == std::vector<unsigned char>({false, false, false}));
+    REQUIRE(config.option<ConfigOptionStrings>("filament_mixed_gradient_range")->values == std::vector<std::string>({"", "", ""}));
+    REQUIRE(config.option<ConfigOptionStrings>("filament_mixed_gradient_curve")->values == std::vector<std::string>({"", "", ""}));
+
+    resize_mixed_filament_metadata(config, 2, 4);
+    REQUIRE(config.option<ConfigOptionBools>("filament_is_mixed")->values == std::vector<unsigned char>({false, false, false, false}));
+    REQUIRE(config.option<ConfigOptionStrings>("filament_mixed_components")->values == std::vector<std::string>({"", "", "", ""}));
+}