Keep a Disabled Filament Override Off After a Restart

A child preset stores "nil" both for an override the user switched off and
for a per-variant column it inherits from its parent, and the loader filled
every nil from the parent. Whenever the parent preset sets Retract Before
Wipe or another override, switching it off lasted only until the next
restart, project open or newer cloud copy.

Treat the keys in is_filament_extruder_override_key, now including the
ironing overrides, as "nil means off": Preset::save and the project-embedded
preset diff write such an option with all its columns, and the loader keeps
its nil columns while still mapping them onto the parent's variants by
name. Every other nullable option keeps nil as "inherit this column". The
cloud diff only force-emits a disabled override whose default is a real
value.

localization/i18n/OrcaSlicer.pot

@@ -10657,6 +10657,9 @@ msgstr ""
 msgid "Send Failed"
 msgstr ""
 
+msgid "No available printers"
+msgstr ""
+
 msgid "The name length exceeds the limit."
 msgstr ""
 

src/libslic3r/Config.hpp

@@ -377,7 +377,8 @@ public:
     virtual void set(const ConfigOption* rhs, size_t start, size_t len)                                                     = 0;
     virtual void set_with_restore(const ConfigOptionVectorBase* rhs, std::vector<int>& restore_index, int stride)           = 0;
     virtual void set_with_restore_2(const ConfigOptionVectorBase* rhs, std::vector<int>& restore_index, int start, int len, bool skip_error = false) = 0;
-    virtual void set_only_diff(const ConfigOptionVectorBase* rhs, std::vector<int>& diff_index, int stride)                 = 0;
+    // keep_nil: copy a nil column from rhs as well, for options whose nil means "disabled" rather than "inherit".
+    virtual void set_only_diff(const ConfigOptionVectorBase* rhs, std::vector<int>& diff_index, int stride, bool keep_nil = false) = 0;
     virtual void set_to_index(const ConfigOptionVectorBase* rhs, std::vector<int>& dest_index, int stride) = 0;
     virtual void set_with_nil(const ConfigOptionVectorBase* rhs, const ConfigOptionVectorBase* inherits, int stride)        = 0;
     // Resize the vector of values, copy the newly added values from opt_default if provided.
@@ -580,7 +581,7 @@ public:
     //set a item related with extruder variants when loading user config, only set the different value of some extruder
     //rhs: item from user config
     //diff_index: which index in this vector need to be set
-    virtual void set_only_diff(const ConfigOptionVectorBase* rhs, std::vector<int>& diff_index, int stride) override
+    virtual void set_only_diff(const ConfigOptionVectorBase* rhs, std::vector<int>& diff_index, int stride, bool keep_nil) override
     {
         if (rhs->type() == this->type()) {
             // Assign the first value of the rhs vector.
@@ -592,7 +593,7 @@ public:
             for (size_t i = 0; i < diff_index.size(); i++) {
                 if (diff_index[i] != -1) {
                     for (size_t j = 0; j < stride; j++) {
-                        if (!other->is_nil(diff_index[i] * stride))
+                        if (keep_nil || !other->is_nil(diff_index[i] * stride))
                             this->values[i * stride + j] = other->values[diff_index[i] * stride + j];
                     }
                 }

src/libslic3r/Format/bbs_3mf.cpp

@@ -988,7 +988,7 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
 
             MetadataList metadata;
             VolumeMetadataList volumes;
-            bool auto_drop { true };
+            std::optional<bool> auto_drop;
         };
 
         struct CutObjectInfo
@@ -1208,6 +1208,7 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
         //IdToGeometryMap m_orig_geometries; // backup & restore
         CurrentConfig m_curr_config;
         IdToMetadataMap m_objects_metadata;
+        std::set<int>   m_items_auto_drop_off; // object ids with a build item auto_drop="0" (2.4.x layout)
         IdToCutObjectInfoMap       m_cut_object_infos;
         IdToLayerHeightsProfileMap m_layer_heights_profiles;
         IdToLayerConfigRangesMap m_layer_config_ranges;
@@ -1463,6 +1464,7 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
         m_objects.clear();
         m_instances.clear();
         m_objects_metadata.clear();
+        m_items_auto_drop_off.clear();
         m_curr_metadata_name.clear();
         m_curr_characters.clear();
 
@@ -1502,6 +1504,7 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
         m_curr_config.object_id = -1;
         m_curr_config.volume_id = -1;
         m_objects_metadata.clear();
+        m_items_auto_drop_off.clear();
         m_layer_heights_profiles.clear();
         m_layer_config_ranges.clear();
         m_brim_ear_points.clear();
@@ -2257,11 +2260,14 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
             ObjectMetadata::VolumeMetadataList volumes;
             ObjectMetadata::VolumeMetadataList* volumes_ptr = nullptr;
 
+            // 2.4.x stored auto_drop on build items, shared by all instances of an object; any "off" wins
+            const bool legacy_auto_drop = !m_items_auto_drop_off.count(object.first.second);
+
             IdToMetadataMap::iterator obj_metadata = m_objects_metadata.find(object.first.second);
             if (obj_metadata != m_objects_metadata.end()) {
                 // config data has been found, this model was saved using slic3r pe
 
-                model_object->auto_drop = obj_metadata->second.auto_drop;
+                model_object->auto_drop = obj_metadata->second.auto_drop.value_or(legacy_auto_drop);
 
                 // apply object's name and config data
                 for (const Metadata& metadata : obj_metadata->second.metadata) {
@@ -2279,6 +2285,7 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
             }
             else {
                 // config data not found, this model was not saved using slic3r pe
+                model_object->auto_drop = legacy_auto_drop;
 
                 // add the entire geometry as the single volume to generate
                 //volumes.emplace_back(0, (int)obj_geometry->second.triangles.size() - 1);
@@ -4121,6 +4128,8 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
         std::string path = bbs_get_attribute_value_string(attributes, num_attributes, PPATH_ATTR);
         Transform3d transform = bbs_get_transform_from_3mf_specs_string(bbs_get_attribute_value_string(attributes, num_attributes, TRANSFORM_ATTR));
         int printable = bbs_get_attribute_value_bool(attributes, num_attributes, PRINTABLE_ATTR);
+        if (const char* auto_drop = bbs_get_attribute_value_charptr(attributes, num_attributes, AUTO_DROP_ATTR); auto_drop != nullptr && !::atoi(auto_drop))
+            m_items_auto_drop_off.insert(object_id);
         return !m_load_model || _create_object_instance(path, object_id, transform, printable, 1);
     }
 
@@ -4489,7 +4498,8 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
         // int instances_count_id = bbs_get_attribute_value_int(attributes, num_attributes, INSTANCESCOUNT_ATTR);
 
         ObjectMetadata metadata;
-        metadata.auto_drop = bbs_get_attribute_value_bool(attributes, num_attributes, AUTO_DROP_ATTR);
+        if (bbs_get_attribute_value_charptr(attributes, num_attributes, AUTO_DROP_ATTR) != nullptr)
+            metadata.auto_drop = bbs_get_attribute_value_bool(attributes, num_attributes, AUTO_DROP_ATTR);
         m_objects_metadata.insert({ object_id, std::move(metadata) });
         m_curr_config.object_id = object_id;
         return true;

src/libslic3r/Preset.cpp

@@ -797,7 +797,7 @@ bool Preset::save(DynamicPrintConfig* parent_config)
         {
             ConfigOption *opt_src = config.option(option);
             ConfigOption *opt_dst = temp_config.option(option, true);
-            if (opt_dst->is_scalar() || !(opt_dst->nullable()))
+            if (opt_dst->is_scalar() || !(opt_dst->nullable()) || is_filament_extruder_override_key(option))
                 opt_dst->set(opt_src);
             else {
                 ConfigOptionVectorBase* opt_vec_src = static_cast<ConfigOptionVectorBase*>(opt_src);
@@ -2131,7 +2131,7 @@ Preset* PresetCollection::get_preset_differed_for_save(Preset& preset)
         {
             ConfigOption *opt_src = preset.config.option(option);
             ConfigOption *opt_dst = temp_config.option(option, true);
-            if (opt_dst->is_scalar() || !(opt_dst->nullable()))
+            if (opt_dst->is_scalar() || !(opt_dst->nullable()) || is_filament_extruder_override_key(option))
                 opt_dst->set(opt_src);
             else {
                 ConfigOptionVectorBase* opt_vec_src = static_cast<ConfigOptionVectorBase*>(opt_src);
@@ -2198,9 +2198,12 @@ int PresetCollection::get_differed_values_to_update(Preset& preset, std::map<std
         // option's non-nil default (e.g. filament_retract_before_wipe -> 100%), silently
         // resurrecting an override the user turned off. See GitHub issue on Retract Before Wipe.
         if (m_type == Preset::TYPE_FILAMENT) {
-            for (const std::string& opt_key : filament_extruder_override_keys) {
-                if (key_values.count(opt_key))
-                    continue; // already carried by the diff
+            for (const std::string& opt_key : preset.config.keys()) {
+                if (!is_filament_extruder_override_key(opt_key) || key_values.count(opt_key))
+                    continue; // not an override, or already carried by the diff
+                const ConfigOptionDef *def = print_config_def.get(opt_key);
+                if (def == nullptr || !def->default_value || def->default_value->is_nil())
+                    continue; // the option's default is nil too, so an absent key cannot come back as a value
                 const auto* opt_vec = dynamic_cast<const ConfigOptionVectorBase*>(preset.config.option(opt_key));
                 if (opt_vec == nullptr)
                     continue;

src/libslic3r/Preset.hpp

@@ -756,7 +756,14 @@ public:
     Preset&         get_edited_preset()         { return m_edited_preset; }
     const Preset&   get_edited_preset() const   { return m_edited_preset; }
 
-    const Preset& get_selected_preset_base() const { return *get_preset_base(m_presets[m_idx_selected]); }
+    // The root of the selected preset's inherits chain, or the selected preset itself when
+    // the chain names a preset that is not loaded (e.g. a vendor that is not installed).
+    const Preset& get_selected_preset_base() const
+    {
+        const Preset &selected = m_presets[m_idx_selected];
+        const Preset *base     = get_preset_base(selected);
+        return base ? *base : selected;
+    }
 
     // Return the last saved preset.
 //  const Preset&   get_saved_preset() const { return m_saved_preset; }

src/libslic3r/PrintConfig.cpp

@@ -119,12 +119,18 @@ const std::vector<std::string> filament_extruder_override_keys = {
 };
 
 // Some filament override parameters are generated from filament_extruder_override_keys,
-// while filament_retract_length_nc is defined separately. Keep the generator list
-// unchanged and use this helper for behavior checks that need the full override set.
+// while filament_retract_length_nc and the ironing overrides are defined separately.
+// Keep the generator list unchanged and use this helper for behavior checks that need
+// the full override set. A nil in one of these keys means the override is disabled, so
+// child presets store and load it verbatim instead of treating nil as "inherit".
 bool is_filament_extruder_override_key(const std::string &opt_key)
 {
     return std::find(filament_extruder_override_keys.begin(), filament_extruder_override_keys.end(), opt_key) != filament_extruder_override_keys.end() ||
-           opt_key == "filament_retract_length_nc";
+           opt_key == "filament_retract_length_nc" ||
+           opt_key == "filament_ironing_flow" ||
+           opt_key == "filament_ironing_spacing" ||
+           opt_key == "filament_ironing_inset" ||
+           opt_key == "filament_ironing_speed";
 }
 
 size_t get_extruder_index(const GCodeConfig& config, unsigned int filament_id)
@@ -12255,7 +12261,8 @@ void DynamicPrintConfig::update_diff_values_to_child_config(DynamicPrintConfig&
                     opt_src->set(opt_target);
                 }
                 else
-                    opt_vec_src->set_only_diff(opt_vec_dest, variant_index, stride);
+                    // An override's nil means "disabled" and is the child's value; every other nil column inherits.
+                    opt_vec_src->set_only_diff(opt_vec_dest, variant_index, stride, is_filament_extruder_override_key(opt));
             }
         }
     }

src/slic3r/GUI/CreatePresetsDialog.cpp

@@ -3151,7 +3151,7 @@ void CreatePrinterPresetDialog::set_current_visible_printer()
     m_printer_name_to_preset.clear();
     for (const Preset &printer_preset : printer_presets) {
         if (!printer_preset.is_visible) continue;
-        if (preset_bundle->printers.get_preset_base(printer_preset)->name != printer_preset.name) continue;
+        if (preset_bundle->printers.get_preset_base(printer_preset) != &printer_preset) continue;
         if (auto printer_model = dynamic_cast<ConfigOptionString*>(const_cast<Preset&>(printer_preset).config.option("printer_model", false))) {
             if (m_printer_name_to_preset.find(printer_model->value) == m_printer_name_to_preset.end()) {
                 printer_choice.push_back(from_u8(printer_model->value));
@@ -4962,7 +4962,7 @@ void CreatePresetForPrinterDialog::get_visible_printer_and_compatible_filament_p
                     if (filament_preset.is_default || !filament_preset.is_compatible || filament_preset.is_project_embedded) continue;
                     ConfigOptionStrings *filament_types;
                     const Preset *       filament_preset_base = m_preset_bundle->filaments.get_preset_base(filament_preset);
-                    if (filament_preset_base == &filament_preset) {
+                    if (filament_preset_base == &filament_preset || filament_preset_base == nullptr) {
                         filament_types = dynamic_cast<ConfigOptionStrings *>(const_cast<Preset *>(&filament_preset)->config.option("filament_type"));
                     } else {
                         filament_types = dynamic_cast<ConfigOptionStrings *>(const_cast<Preset *>(filament_preset_base)->config.option("filament_type"));

src/slic3r/GUI/SelectMachine.cpp

@@ -4087,7 +4087,7 @@ void SelectMachineDialog::update_user_printer()
     {
         m_printer_last_select = "";
         update_select_layout(nullptr);
-        m_printer_box->GetPrinterComboBox()->SetTextLabel("");
+        m_printer_box->GetPrinterComboBox()->SetValue(_L("No available printers"));
     }
 
     BOOST_LOG_TRIVIAL(info) << __FUNCTION__ << "for send task, current printer id =  " << m_printer_last_select << std::endl;

src/slic3r/GUI/SendToPrinter.cpp

@@ -1229,7 +1229,7 @@ void SendToPrinterDialog::update_user_printer()
     }
     else {
         m_printer_last_select = "";
-        m_comboBox_printer->SetTextLabel("");
+        m_comboBox_printer->SetValue(_L("No available printers"));
     }
 
     BOOST_LOG_TRIVIAL(info) << __FUNCTION__ << "for send task, current printer id =  " << m_printer_last_select << std::endl;

src/slic3r/GUI/Widgets/ComboBox.cpp

@@ -287,7 +287,7 @@ void ComboBox::DoDeleteOneItem(unsigned int pos)
 
 void ComboBox::ForceDropdownOpen()
 {
-    if (!IsEnabled())
+    if (!IsEnabled() || items.empty())
         return;
 
     if (!drop_down) {
@@ -398,7 +398,7 @@ void ComboBox::mouseDown(wxMouseEvent &event)
     SetFocus();
     if (drop_down) {
         drop.Hide();
-    } else if (drop.HasDismissLongTime()) {
+    } else if (!items.empty() && drop.HasDismissLongTime()) { // DropDown paints nothing for an empty list
         drop.autoPosition();
         drop_down = true;
         drop.Popup(&drop);
@@ -426,7 +426,7 @@ void ComboBox::keyDown(wxKeyEvent& event)
         case WXK_SPACE:
             if (drop_down) {
                 drop.DismissAndNotify();
-            } else if (drop.HasDismissLongTime()) {
+            } else if (!items.empty() && drop.HasDismissLongTime()) {
                 drop.autoPosition();
                 drop_down = true;
                 drop.Popup();

src/slic3r/plugin/PythonInterpreter.cpp

@@ -584,6 +584,19 @@ bool PythonInterpreter::initialize()
         }
         BOOST_LOG_TRIVIAL(debug) << "Program name set successfully";
 
+        // Keep bytecode out of the Python home. The shipped .pyc files are stale against their
+        // sources, so a writable install would rewrite them inside the app (breaking a signed
+        // macOS bundle's seal) and a read-only one would recompile them on every launch.
+        const std::string pycache_prefix = data_dir() + "/python/pycache";
+#ifdef _WIN32
+        status = PyConfig_SetString(&config, &config.pycache_prefix, boost::nowide::widen(pycache_prefix).c_str());
+#else
+        status = PyConfig_SetBytesString(&config, &config.pycache_prefix, pycache_prefix.c_str());
+#endif
+        if (PyStatus_Exception(status))
+            BOOST_LOG_TRIVIAL(warning) << "Failed to set the Python bytecode cache to " << pycache_prefix << ": "
+                                       << (status.err_msg ? status.err_msg : "unknown error");
+
         // Use pybind11's scoped_interpreter which properly initializes
         // pybind11 internals for multi-threaded use — raw Py_InitializeFromConfig
         // does not set up thread state tracking that pybind11 requires.

tests/libslic3r/test_3mf.cpp

@@ -505,6 +505,28 @@ TEST_CASE("A project whose components reference themselves fails to load", "[3mf
     REQUIRE_FALSE(loaded);
 }
 
+TEST_CASE("A project in the 2.4.x layout keeps auto drop off from its build item", "[3mf][Regression]")
+{
+    // 2.4.x wrote auto_drop on the build item and left it off the object, so the object is re-laid out here.
+    ScopedTemporaryFile temp(".3mf");
+    {
+        Model        model;
+        ModelObject* object = model.add_object();
+        object->add_volume(make_cube(10., 10., 10.));
+        object->add_instance();
+        object->auto_drop = false;
+        store_project(model, temp.string(), SaveStrategy::Zip64 | SaveStrategy::Silence);
+    }
+    REQUIRE(replace_in_3mf_entry(temp.string(), "model_settings.config", " auto_drop=\"0\"", ""));
+    REQUIRE(replace_in_3mf_entry(temp.string(), "3dmodel.model", "printable=\"1\"/>", "printable=\"1\" auto_drop=\"0\"/>"));
+
+    ScopedTemporaryDir backup_dir("orca_auto_drop_dst");
+    Model              model;
+    REQUIRE(load_project(temp.string(), model, backup_dir));
+    REQUIRE(model.objects.size() == 1);
+    CHECK_FALSE(model.objects.front()->auto_drop);
+}
+
 TEST_CASE("An object loads up to the component reference budget and fails past it", "[3mf][Regression]")
 {
     // The importer queues at most 100000 component references per object. Every reference besides the

tests/libslic3r/test_config.cpp

@@ -1665,3 +1665,75 @@ TEST_CASE("Default options of enum lists get their definition's keys map", "[Con
     }
     CHECK(enum_lists > 0);
 }
+
+TEST_CASE("A disabled filament override survives the merge with a parent that sets it", "[Config][Variant]")
+{
+    std::set<std::string>      no_keys;
+    Slic3r::DynamicPrintConfig parent;
+    parent.set_deserialize_strict("filament_retract_before_wipe", "100%");
+    parent.set_deserialize_strict("filament_ironing_flow", "15%");
+    Slic3r::DynamicPrintConfig child;
+    child.set_deserialize_strict("filament_retract_before_wipe", "nil");
+    child.set_deserialize_strict("filament_ironing_flow", "nil");
+    parent.update_diff_values_to_child_config(child, "", "filament_extruder_variant",
+                                              Slic3r::filament_options_with_variant, no_keys);
+    CHECK(parent.opt_serialize("filament_retract_before_wipe") == "nil");
+    CHECK(parent.opt_serialize("filament_ironing_flow") == "nil");
+}
+
+SCENARIO("A two-variant child's disabled override column is matched to the parent's variant by name", "[Config][Variant]")
+{
+    std::set<std::string> no_keys;
+    GIVEN("A two-variant filament parent") {
+        Slic3r::DynamicPrintConfig parent;
+        parent.set_deserialize_strict("filament_extruder_variant", "Direct Drive Standard;Direct Drive High Flow");
+        parent.set_deserialize_strict("filament_retract_before_wipe", "100%,100%");
+        parent.set_deserialize_strict("filament_flow_ratio", "1,1");
+        WHEN("the child disables the override on one variant and leaves a plain option nil on it") {
+            Slic3r::DynamicPrintConfig child;
+            child.set_deserialize_strict("filament_extruder_variant", "Direct Drive Standard;Direct Drive High Flow");
+            child.set_deserialize_strict("filament_retract_before_wipe", "nil,100%");
+            child.set_deserialize_strict("filament_flow_ratio", "nil,1.1");
+            parent.update_diff_values_to_child_config(child, "", "filament_extruder_variant",
+                                                      Slic3r::filament_options_with_variant, no_keys);
+            THEN("the override column is disabled while the plain option's nil column inherits") {
+                CHECK(parent.opt_serialize("filament_retract_before_wipe") == "nil,100%");
+                CHECK(parent.opt_serialize("filament_flow_ratio") == "1,1.1");
+            }
+        }
+        WHEN("the child lists the same variants in the other order") {
+            Slic3r::DynamicPrintConfig child;
+            child.set_deserialize_strict("filament_extruder_variant", "Direct Drive High Flow;Direct Drive Standard");
+            child.set_deserialize_strict("filament_retract_before_wipe", "70%,nil");
+            child.set_deserialize_strict("filament_flow_ratio", "1.1,nil");
+            parent.update_diff_values_to_child_config(child, "", "filament_extruder_variant",
+                                                      Slic3r::filament_options_with_variant, no_keys);
+            THEN("columns are matched by variant name, the disabled one included") {
+                CHECK(parent.opt_serialize("filament_retract_before_wipe") == "nil,70%");
+                CHECK(parent.opt_serialize("filament_flow_ratio") == "1,1.1");
+            }
+        }
+        WHEN("the child was saved with a single variant") {
+            Slic3r::DynamicPrintConfig child;
+            child.set_deserialize_strict("filament_extruder_variant", "Direct Drive Standard");
+            child.set_deserialize_strict("filament_retract_before_wipe", "nil");
+            parent.update_diff_values_to_child_config(child, "", "filament_extruder_variant",
+                                                      Slic3r::filament_options_with_variant, no_keys);
+            THEN("its one value applies to every variant of that extruder, as slicing does") {
+                CHECK(parent.opt_serialize("filament_retract_before_wipe") == "nil,nil");
+            }
+        }
+    }
+}
+
+TEST_CASE("Every listed filament override is nullable", "[Config]")
+{
+    std::set<std::string> overrides(Slic3r::filament_extruder_override_keys.begin(), Slic3r::filament_extruder_override_keys.end());
+    overrides.insert({ "filament_retract_length_nc", "filament_ironing_flow", "filament_ironing_spacing", "filament_ironing_inset", "filament_ironing_speed" });
+    for (const auto &[key, def] : Slic3r::print_config_def.options) {
+        INFO(key);
+        CHECK(Slic3r::is_filament_extruder_override_key(key) == (overrides.count(key) == 1));
+        if (overrides.count(key) == 1)
+            CHECK(def.nullable);
+    }
+}

tests/libslic3r/test_preset_bundle_loading.cpp

@@ -1219,6 +1219,24 @@ TEST_CASE("find_preset2 auto-matches removed Generic vendor profiles to the libr
     CHECK(bundle.filaments.find_preset2("BrandX Generic PETG", /*auto_match=*/true) == nullptr);
 }
 
+TEST_CASE("The selected preset is its own base when its parent is not loaded", "[Preset]")
+{
+    PresetCollection printers(Preset::TYPE_PRINTER, Preset::printer_options(),
+                              static_cast<const PrintRegionConfig &>(FullPrintConfig::defaults()));
+    add_inmemory_preset(printers, "Printer");
+    add_inmemory_preset(printers, "User Printer", "Printer");
+    add_inmemory_preset(printers, "Orphan Printer", "Uninstalled Vendor Printer");
+
+    printers.select_preset_by_name("User Printer", true);
+    REQUIRE(printers.get_selected_preset_name() == "User Printer");
+    CHECK(printers.get_selected_preset_base().name == "Printer");
+
+    printers.select_preset_by_name("Orphan Printer", true);
+    REQUIRE(printers.get_selected_preset_name() == "Orphan Printer");
+    REQUIRE(printers.get_preset_base(printers.get_selected_preset()) == nullptr);
+    CHECK(printers.get_selected_preset_base().name == "Orphan Printer");
+}
+
 TEST_CASE("Renamed parent is normalized into a loaded preset's inherits", "[Preset][Rename]")
 {
     ScopedTemporaryDir   temp_dir;
@@ -8399,3 +8417,58 @@ TEST_CASE("An empty choice list in a G-code's settings keeps the value it had be
     CHECK(config.opt_serialize("nozzle_volume_type") == "High Flow");
     CHECK(config.option<ConfigOptionStrings>("filament_multi_colour")->values.empty());
 }
+
+TEST_CASE("A disabled filament override is saved and reloaded column by column", "[Preset][Bundle]")
+{
+    ScopedPresetDataDir data_dir;
+    PresetBundle        bundle;
+
+    Preset &parent = add_inmemory_preset(bundle.filaments, "Parent PLA @System");
+    parent.config.option<ConfigOptionStrings>("filament_extruder_variant", true)->values = { "Direct Drive Standard", "Direct Drive High Flow" };
+    parent.config.option<ConfigOptionPercentsNullable>("filament_retract_before_wipe", true)->values = { 100., 100. };
+    parent.config.option<ConfigOptionFloatsNullable>("filament_flow_ratio", true)->values = { 1., 1. };
+
+    // The child turns the override off on the first variant and changes a plain option on the second.
+    const fs::path file = data_dir.tmp.path() / PRESET_FILAMENT_NAME / "Child PLA.json";
+    Preset         child(Preset::TYPE_FILAMENT, "Child PLA");
+    child.file    = file.string();
+    child.version = *Semver::parse("1.0.0");
+    child.config  = parent.config;
+    child.config.option<ConfigOptionString>(BBL_JSON_KEY_INHERITS, true)->value = parent.name;
+    child.config.option<ConfigOptionPercentsNullable>("filament_retract_before_wipe")->set_at_to_nil(0);
+    child.config.option<ConfigOptionFloatsNullable>("filament_flow_ratio")->values = { 1., 1.1 };
+    REQUIRE(child.save(&parent.config));
+
+    // On disk the override keeps every column, so its nil can only mean "off"; a plain
+    // option still stores nil for the columns that match the parent.
+    DynamicPrintConfig                 saved;
+    std::map<std::string, std::string> key_values;
+    std::string                        reason;
+    saved.load_from_json(file.string(), ForwardCompatibilitySubstitutionRule::EnableSilent, key_values, reason);
+    REQUIRE(reason.empty());
+    CHECK(saved.opt_serialize("filament_retract_before_wipe") == "nil,100%");
+    CHECK(saved.opt_serialize("filament_flow_ratio") == "nil,1.1");
+
+    PresetsConfigSubstitutions substitutions;
+    bundle.filaments.load_presets(data_dir.tmp.path().string(), PRESET_FILAMENT_NAME, substitutions,
+                                  ForwardCompatibilitySubstitutionRule::EnableSilent);
+    const Preset *loaded = bundle.filaments.find_preset("Child PLA");
+    REQUIRE(loaded != nullptr);
+    CHECK(loaded->config.opt_serialize("filament_retract_before_wipe") == "nil,100%");
+    CHECK(loaded->config.opt_serialize("filament_flow_ratio") == "1,1.1");
+}
+
+TEST_CASE("The cloud diff force-emits a disabled override only where the cloud would fill a value in", "[Preset][Bundle]")
+{
+    PresetBundle bundle;
+    add_inmemory_preset(bundle.filaments, "Parent PLA @System");
+    Preset &child = add_inmemory_preset(bundle.filaments, "Child PLA", "Parent PLA @System");
+    // Every override is nil in both parent and child, so none is in the plain diff.
+    std::map<std::string, std::string> key_values;
+    REQUIRE(bundle.filaments.get_differed_values_to_update(child, key_values) >= 0);
+    // Retract Before Wipe defaults to 100%: an absent key would come back as 100%, so nil is sent.
+    CHECK(key_values.count("filament_retract_before_wipe") == 1);
+    CHECK(key_values["filament_retract_before_wipe"] == "nil");
+    // An ironing override defaults to nil: an absent key stays nil, so it is not sent.
+    CHECK(key_values.count("filament_ironing_flow") == 0);
+}

tests/slic3rutils/test_moonraker_printer_agent.cpp

@@ -150,6 +150,13 @@ public:
         return m_close_frames;
     }
 
+    // The printer answers a close frame before its own read completes, so the agent's stop can return first.
+    bool wait_for_close_frames(int count)
+    {
+        std::unique_lock<std::mutex> lock(m_mutex);
+        return m_changed.wait_for(lock, 10s, [&] { return m_close_frames >= count; });
+    }
+
     // Hangs up every connection that is waiting.
     void release()
     {
@@ -277,6 +284,7 @@ private:
                 if (ec == websocket::error::closed) {
                     std::lock_guard<std::mutex> lock(m_mutex);
                     ++m_close_frames;
+                    m_changed.notify_all();
                 }
                 if (ec)
                     reading = false;
@@ -449,6 +457,7 @@ TEST_CASE("Stopping the status stream sends the printer a close frame", "[Moonra
     REQUIRE(f.printer.wait_for_ready_connections(1));
 
     CHECK(f.stops_within(3s));
+    CHECK(f.printer.wait_for_close_frames(1));
     CHECK(f.printer.close_frames() == 1);
 }
 

tests/slic3rutils/test_plugin_lifecycle.cpp

@@ -615,8 +615,22 @@ TEST_CASE("Python module release removes package submodules and owned sys.path",
 
     // Ensure the next import executes the new submodule rather than reusing a stale package child.
     write_package("'new'");
-    boost::system::error_code ec;
-    fs::remove_all(package_root / "__pycache__", ec);
+    {
+        // The rewrite can keep the old mtime and size, so drop the bytecode wherever the
+        // interpreter caches it.
+        PythonGILState gil;
+        REQUIRE(gil);
+        PyObjectPtr util(PyImport_ImportModule("importlib.util"));
+        REQUIRE(util);
+        for (const char* file : {"__init__.py", "sub.py"}) {
+            PyObjectPtr source(PyUnicode_DecodeFSDefault((package_root / file).string().c_str()));
+            REQUIRE(source);
+            PyObjectPtr cached(PyObject_CallMethod(util.get(), "cache_from_source", "O", source.get()));
+            REQUIRE(cached);
+            boost::system::error_code ec;
+            fs::remove(fs::path(PyUnicode_AsUTF8(cached.get())), ec);
+        }
+    }
 
     paths.clear();
     modules.clear();