Fix plugin configuration not taking effect, and improve the plugin config UI (#14944)

# Description

Changing a slicing plugin's configuration had no effect on the sliced
result until you forced a re-slice some other way; it now applies
immediately. Print, printer and filament presets also keep their plugin
configuration separately, so configuring a plugin on one no longer wipes
out what you set on another.

A plugin's custom configuration page gets the same round of improvements
in both the Plugins dialog and the per-preset dialog: it follows the
app's light/dark theme, keeps its state while you edit instead of
resetting under the cursor, and can tell whether it is being edited
globally or for a preset, so "Restore defaults" can be labeled for what
it will actually do. The two bundled examples show this off — Twistify
now ships a custom configuration UI, and Inspector is themed, groups

# Screenshots/Recordings/Graphs



https://github.com/user-attachments/assets/02ca062a-5143-49a3-abe0-a2a040b3a928



## Tests

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src/libslic3r/Preset.cpp

@@ -1203,7 +1203,7 @@ static std::vector<std::string> s_Preset_print_options{
     "post_process",
     "slicing_pipeline_plugin",
     "plugins",
-    "plugin_config_overrides",
+    "print_plugin_config_overrides",
     "process_change_extrusion_role_gcode",
     "min_length_factor",
     "wall_maximum_resolution",
@@ -1378,7 +1378,7 @@ static std::vector<std::string> s_Preset_filament_options {/*"filament_colour",
     "filament_preheat_temperature_delta", "filament_retract_length_nc",
     "filament_change_length_nc", "filament_prime_volume", "filament_prime_volume_nc",
     "long_retractions_when_ec", "retraction_distances_when_ec",
-    "plugin_config_overrides",
+    "filament_plugin_config_overrides",
     //ams chamber
     "filament_dev_ams_drying_ams_limitations", "filament_dev_ams_drying_temperature", "filament_dev_ams_drying_time", "filament_dev_ams_drying_heat_distortion_temperature",
     "filament_dev_chamber_drying_bed_temperature", "filament_dev_chamber_drying_time",
@@ -1430,7 +1430,7 @@ static std::vector<std::string> s_Preset_printer_options {
     // Fast-purge printer flag + device/firmware-facing per-variant extruder-change
     // deretraction speed (unconsumed by the slicer; carried by H2D/A2L/X2D/P2S machine profiles).
     "support_fast_purge_mode", "deretract_speed_extruder_change",
-    "plugin_config_overrides"
+    "printer_plugin_config_overrides"
     };
 
 static std::vector<std::string> s_Preset_sla_print_options {
@@ -1542,6 +1542,15 @@ const std::vector<std::string>& Preset::printer_options()
     return s_opts;
 }
 
+const char* Preset::plugin_overrides_key(Type type)
+{
+    switch (type) {
+    case TYPE_PRINTER:  return "printer_plugin_config_overrides";
+    case TYPE_FILAMENT: return "filament_plugin_config_overrides";
+    default:            return "print_plugin_config_overrides";
+    }
+}
+
 PresetCollection::PresetCollection(Preset::Type type, const std::vector<std::string> &keys, const Slic3r::StaticPrintConfig &defaults, const std::string &default_name) :
     m_type(type),
     m_edited_preset(type, "", false),

src/libslic3r/Preset.hpp

@@ -407,6 +407,11 @@ public:
     // Printer machine limits, those are contained in printer_options().
     static const std::vector<std::string>&  machine_limits_options();
 
+    // Option key holding this preset type's plugin capability overrides. Each type has its own key so
+    // the values survive the merge into a single full config; print is the fallback for the types with
+    // no plugin-backed options.
+    static const char*                      plugin_overrides_key(Type type);
+
     static const std::vector<std::string>&  sla_printer_options();
     static const std::vector<std::string>&  sla_material_options();
     static const std::vector<std::string>&  sla_print_options();

src/libslic3r/Print.cpp

@@ -285,6 +285,7 @@ bool Print::invalidate_state_by_config_options(const ConfigOptionResolver & /* n
             steps.emplace_back(psSkirtBrim);
         } else if (
                opt_key == "slicing_pipeline_plugin"
+            || opt_key == "print_plugin_config_overrides"
             || opt_key == "initial_layer_print_height"
             || opt_key == "nozzle_diameter"
             || opt_key == "filament_shrink"

src/libslic3r/PrintConfig.cpp

@@ -1081,16 +1081,21 @@ void PrintConfigDef::init_common_params()
         def->set_default_value(new ConfigOptionString());
     }
 
-    def = this->add("plugin_config_overrides", coString);
-    def->label = L("Capabilities");
-    def->tooltip = L("Configuration for the plugin capabilities this preset uses, overriding the global "
-                     "Capabilities configuration. Stored as a raw JSON array and edited through the dialog "
-                     "behind the button, never typed in directly.");
-    // Never shown as a text field: GUIType::plugin_config renders a button that opens PluginsConfigDialog.
-    def->gui_type = ConfigOptionDef::GUIType::plugin_config;
-    def->mode = comAdvanced;
-    def->cli = ConfigOptionDef::nocli;
-    def->set_default_value(new ConfigOptionString(""));
+    // One key per preset type (Preset::plugin_overrides_key), so the print, printer and filament
+    // overrides don't clobber each other when the presets merge into one full config. No handle_legacy
+    // migration from the shared "plugin_config_overrides" they replace: it only ever shipped in
+    // nightlies. Never a text field — GUIType::plugin_config renders a button opening PluginsConfigDialog.
+    for (const char* key : {"print_plugin_config_overrides", "printer_plugin_config_overrides", "filament_plugin_config_overrides"}) {
+        def = this->add(key, coString);
+        def->label = L("Capabilities");
+        def->tooltip = L("Configuration for the plugin capabilities this preset uses, overriding the global "
+                         "Capabilities configuration. Stored as a raw JSON array and edited through the dialog "
+                         "behind the button, never typed in directly.");
+        def->gui_type = ConfigOptionDef::GUIType::plugin_config;
+        def->mode = comAdvanced;
+        def->cli = ConfigOptionDef::nocli;
+        def->set_default_value(new ConfigOptionString(""));
+    }
 }
 
 void PrintConfigDef::init_fff_params()

src/libslic3r/PrintConfig.hpp

@@ -1780,6 +1780,7 @@ PRINT_CONFIG_CLASS_DERIVED_DEFINE(
     ((ConfigOptionString,             filename_format))
     ((ConfigOptionStrings,            post_process))
     ((ConfigOptionStrings,            slicing_pipeline_plugin))
+    ((ConfigOptionString,             print_plugin_config_overrides))
     ((ConfigOptionString,             printer_model))
     ((ConfigOptionFloat,              resolution))
     ((ConfigOptionFloats,             retraction_minimum_travel))

src/slic3r/GUI/Tab.cpp

@@ -1796,7 +1796,7 @@ void Tab::on_value_change(const std::string& opt_key, const boost::any& value)
 
     // Keep this preset's "plugins" manifest in sync when a plugin picker changes, so full_config() and
     // save_to_json() always find resolved "name;uuid;capability" references and rebuild it nowhere else.
-    // Also drop any plugin_config_overrides entries for a capability the change just stopped
+    // Also drop any plugin config override entries for a capability the change just stopped
     // referencing (e.g. a plugin removed from slicing_pipeline_plugin), so a saved preset never
     // carries configuration for a capability it no longer names. The Configure button is a separate
     // field holding its own cached copy of that value, so it needs to be told explicitly, or it
@@ -1804,9 +1804,10 @@ void Tab::on_value_change(const std::string& opt_key, const boost::any& value)
     if (const ConfigOptionDef* opt_def = m_config->def()->get(opt_key);
         opt_def && opt_def->is_plugin_backed()) {
         m_config->update_plugin_manifest();
-        if (prune_stale_plugin_overrides(*m_config)) {
-            if (Field* overrides_field = get_field(PLUGIN_OVERRIDES_OPTION_KEY))
-                overrides_field->set_value(boost::any(m_config->opt_string(PLUGIN_OVERRIDES_OPTION_KEY)), false);
+        const std::string overrides_key = Preset::plugin_overrides_key(m_type);
+        if (prune_stale_plugin_overrides(*m_config, overrides_key)) {
+            if (Field* overrides_field = get_field(overrides_key))
+                overrides_field->set_value(boost::any(m_config->opt_string(overrides_key)), false);
         }
     }
 
@@ -3136,7 +3137,7 @@ void TabPrint::build()
         // Its own group: the one above hides its labels, and this row needs its label — and the revert
         // arrow beside it — to show. No label-width override either, as a 0 there means "no label column".
         optgroup = page->new_optgroup(L("Plugin Configuration"), L"param_gcode");
-        optgroup->append_single_option_line("plugin_config_overrides");
+        optgroup->append_single_option_line("print_plugin_config_overrides");
 
         optgroup = page->new_optgroup(L("Notes"), "note", 0);
         option = optgroup->get_option("notes");
@@ -4552,7 +4553,7 @@ void TabFilament::build()
         optgroup->append_single_option_line(option);
 
         optgroup = page->new_optgroup(L("Plugin Configuration"), L"param_gcode");
-        optgroup->append_single_option_line("plugin_config_overrides");
+        optgroup->append_single_option_line("filament_plugin_config_overrides");
 
     page = add_options_page(L("Multimaterial"), "custom-gcode_multi_material"); // ORCA: icon only visible on placeholders
         optgroup = page->new_optgroup(L("Wipe tower parameters"), "param_tower");
@@ -5061,7 +5062,7 @@ void TabPrinter::build_fff()
         optgroup->append_single_option_line("time_cost", "printer_basic_information_advanced#time-cost");
 
         optgroup = page->new_optgroup(L("Plugin Configuration"), L"param_gcode");
-        optgroup->append_single_option_line("plugin_config_overrides");
+        optgroup->append_single_option_line("printer_plugin_config_overrides");
 
         optgroup  = page->new_optgroup(L("Cooling Fan"), "param_cooling_fan");
         Line line = Line{ L("Fan speed-up time"), optgroup->get_option("fan_speedup_time").opt.tooltip };

src/slic3r/plugin/PluginConfig.cpp

@@ -324,12 +324,6 @@ bool PluginConfig::dirty() const
     return m_dirty;
 }
 
-std::string plugin_overrides_of(const Preset& preset)
-{
-    const auto* opt = dynamic_cast<const ConfigOptionString*>(preset.config.option(PLUGIN_OVERRIDES_OPTION_KEY));
-    return opt == nullptr ? std::string() : opt->value;
-}
-
 bool parse_plugin_overrides(const std::string& raw, CapabilityConfigDocument& document, std::string& error)
 {
     document = CapabilityConfigDocument();
@@ -357,9 +351,9 @@ std::string serialize_plugin_overrides(const CapabilityConfigDocument& document)
     return document.empty() ? std::string() : document.serialize_entries().dump();
 }
 
-bool prune_stale_plugin_overrides(DynamicConfig& config)
+bool prune_stale_plugin_overrides(DynamicConfig& config, const std::string& overrides_key)
 {
-    const auto* overrides_opt = dynamic_cast<const ConfigOptionString*>(config.option(PLUGIN_OVERRIDES_OPTION_KEY));
+    const auto* overrides_opt = dynamic_cast<const ConfigOptionString*>(config.option(overrides_key));
     if (overrides_opt == nullptr || overrides_opt->value.empty())
         return false;
 
@@ -397,7 +391,7 @@ bool prune_stale_plugin_overrides(DynamicConfig& config)
     if (!overrides.prune_unreferenced(referenced))
         return false;
 
-    config.set_key_value(PLUGIN_OVERRIDES_OPTION_KEY, new ConfigOptionString(serialize_plugin_overrides(overrides)));
+    config.set_key_value(overrides_key, new ConfigOptionString(serialize_plugin_overrides(overrides)));
     return true;
 }
 
@@ -470,27 +464,29 @@ EffectiveCapabilityConfig active_capability_config(const PluginCapabilityId& id)
 
     if (bundle != nullptr) {
         const std::string type_key = plugin_capability_type_to_string(id.type);
+        // The edited preset of each type that can hold plugin-backed options, keyed by its option list.
+        const std::pair<const std::vector<std::string>*, const Preset*> scopes[] = {
+            {&Preset::print_options(),    &bundle->prints.get_edited_preset()},
+            {&Preset::printer_options(),  &bundle->printers.get_edited_preset()},
+            {&Preset::filament_options(), &bundle->filaments.get_edited_preset()},
+        };
         for (const auto& [key, def] : print_config_def.options) {
             if (def.plugin_type != type_key)
                 continue;
-
-            const auto& print_options = Preset::print_options();
-            if (std::find(print_options.begin(), print_options.end(), key) != print_options.end()) {
-                preset = &bundle->prints.get_edited_preset();
+            for (const auto& [options, edited] : scopes)
+                if (contains(*options, key)) {
+                    preset = edited;
+                    break;
+                }
+            if (preset != nullptr)
                 break;
-            }
-
-            const auto& printer_options = Preset::printer_options();
-            if (std::find(printer_options.begin(), printer_options.end(), key) != printer_options.end()) {
-                preset = &bundle->printers.get_edited_preset();
-                break;
-            }
         }
     }
 
     if (preset != nullptr) {
+        const auto* stored = dynamic_cast<const ConfigOptionString*>(preset->config.option(Preset::plugin_overrides_key(preset->type)));
         std::string error;
-        if (!parse_plugin_overrides(plugin_overrides_of(*preset), overrides, error)) {
+        if (!parse_plugin_overrides(stored == nullptr ? std::string() : stored->value, overrides, error)) {
             // Text we cannot read is not an override: log it and resolve against the base config.
             BOOST_LOG_TRIVIAL(error) << "Preset \"" << preset->name << "\": " << error;
             overrides = CapabilityConfigDocument();

src/slic3r/plugin/PluginConfig.hpp

@@ -17,7 +17,6 @@
 
 namespace Slic3r {
 
-class Preset;
 class DynamicConfig;
 struct CapabilityConfigEntry
 {
@@ -50,19 +49,15 @@ private:
     std::vector<nlohmann::json>                  m_opaque_entries;
 };
 
-inline constexpr const char* PLUGIN_OVERRIDES_OPTION_KEY = "plugin_config_overrides";
-
-std::string plugin_overrides_of(const Preset& preset);
 bool parse_plugin_overrides(const std::string& raw, CapabilityConfigDocument& document, std::string& error);
 std::string serialize_plugin_overrides(const CapabilityConfigDocument& document);
 
-// Drops plugin_config_overrides entries for capabilities no longer named by any plugin-backed
-// option's current value in `config` (e.g. slicing_pipeline_plugin cleared or switched to a
-// different capability), and writes the result back if anything changed. Called wherever a
-// plugin-backed option's value changes, so a saved preset never carries configuration for a
-// capability it no longer references. Returns true if `config` was modified, so a caller holding a
-// GUI field over PLUGIN_OVERRIDES_OPTION_KEY knows it must refresh that field's displayed value.
-bool prune_stale_plugin_overrides(DynamicConfig& config);
+// Drops override entries for capabilities no longer named by any plugin-backed option in `config`
+// (e.g. slicing_pipeline_plugin cleared or pointed at another capability) and writes the result back
+// to `overrides_key`. Call it wherever such an option changes, so a saved preset never carries
+// configuration for a capability it no longer references. Returns true if `config` was modified, so a
+// caller holding a GUI field over `overrides_key` knows to refresh it.
+bool prune_stale_plugin_overrides(DynamicConfig& config, const std::string& overrides_key);
 
 struct EffectiveCapabilityConfig
 {