Scope plugin config overrides per preset type

Replace the shared plugin_config_overrides key with print/printer/filament
scoped keys so merging presets into one full config cannot clobber an edited
override, letting a slicing plugin config change invalidate the slice step.

resources/web/dialog/PluginsConfigDialog/index.js

@@ -9,10 +9,12 @@ let selectedCapabilityType = "";
 let selectedHasPresetOverride = false;
 let selectedReadOnly = false;
 
-// Identity of the capability whose custom UI is currently loaded in the frame. Saving re-sends the
+// Whether the frame holds the selected capability's custom UI. Payloads are gated by
-// whole capability_config payload, and rebuilding the frame from it would reload the plugin's page
+// IsCurrentCapability and every selection change clears the view, so a loaded frame is always the
-// under the user's cursor; when this still matches, the new values are posted in instead.
+// selected capability's. Saving re-sends the whole capability_config payload, and rebuilding the
-let customFrameKey = "";
+// frame from it would reload the plugin's page under the user's cursor; while the frame is loaded,
+// the new values are posted in instead.
+let customFrameLoaded = false;
 
 function SafeJsonParse(text) {
   try {
@@ -173,10 +175,6 @@ function IsCurrentCapability(payload) {
     && String(payload?.capability_type || "") === selectedCapabilityType;
 }
 
-function CapabilityKey(payload) {
-  return JSON.stringify([payload?.plugin_key, payload?.capability_name, payload?.capability_type]);
-}
-
 function RequestCapabilityConfig() {
   if (!selectedPluginKey || !selectedCapabilityName)
     return;
@@ -202,7 +200,7 @@ function ClearCapabilityConfigView() {
   if (custom) {
     custom.hidden = true;
     custom.removeAttribute("srcdoc");
-    customFrameKey = "";
+    customFrameLoaded = false;
   }
   if (text)
     text.value = "";
@@ -260,10 +258,10 @@ function ApplyCapabilityConfig(payload) {
     if (custom) {
       const context = OrcaConfigContext(payload, "preset");
       custom.hidden = false;
-      if (customFrameKey === CapabilityKey(payload) && custom.contentWindow) {
+      if (customFrameLoaded && custom.contentWindow) {
         custom.contentWindow.postMessage({ __orca: "config", config: config, context: context }, "*");
       } else {
-        customFrameKey = CapabilityKey(payload);
+        customFrameLoaded = true;
         custom.srcdoc = BuildCustomConfigDocument(html, config, context);
       }
     }
@@ -276,7 +274,7 @@ function ApplyCapabilityConfig(payload) {
   if (custom) {
     custom.hidden = true;
     custom.removeAttribute("srcdoc");
-    customFrameKey = "";
+    customFrameLoaded = false;
   }
   if (editor)
     editor.hidden = false;
@@ -416,7 +414,7 @@ document.addEventListener("DOMContentLoaded", () => {
   // OnCustomConfigMessage matches on the frame's contentWindow, not the origin ("null" when
   // sandboxed), and ignores anything else.
   window.addEventListener("message", OnCustomConfigMessage);
-  OrcaWatchThemeForFrame(() => document.getElementById("configCustom"));
+  OrcaWatchThemeForFrame("configCustom");
 
   SendMessage("request_capabilities");
 });

resources/web/dialog/PluginsDialog/index.js

@@ -90,7 +90,7 @@ function OnInit() {
   // OnCustomConfigMessage matches on the frame's contentWindow, not the origin ("null" when
   // sandboxed), and ignores anything else.
   window.addEventListener("message", OnCustomConfigMessage);
-  OrcaWatchThemeForFrame(() => document.getElementById("configCustom"));
+  OrcaWatchThemeForFrame("configCustom");
 
   document.addEventListener("click", (event) => {
     if (!event.target.closest(".ctx"))

resources/web/dialog/js/plugin-config-ui.js

@@ -3,41 +3,25 @@
 // opaque origin, so this bridge is its only channel, and both must offer plugin authors exactly the
 // same one — hence a single module rather than a copy per dialog.
 
-// The host theme "contract" (WebViewHostDialog::host_theme_vars_css). The document-start injector
+// The host theme "contract" (WebViewHostDialog::host_theme_vars_css) arrives as a complete
-// stamps it on the top-level page only — it returns early in child frames — so a sandboxed config UI
+// ":root{--orca-*;color-scheme:...}" rule in the injected <style id="orca-host-theme-vars">, which
-// never sees it unless we hand it over.
+// the document-start injector stamps on the top-level page only — it returns early in child frames —
-const ORCA_THEME_VARS = [
+// so a sandboxed config UI never sees it unless we hand it over. Relay that host-authored CSS
-  "--orca-bg",
+// verbatim rather than re-deriving it variable by variable: the C++ function stays the only place
-  "--orca-fg",
+// the contract is spelled out, and the host re-themes the style in place, so reading it now always
-  "--orca-muted",
+// yields the live theme.
-  "--orca-border",
-  "--orca-accent",
-  "--orca-accent-fg",
-  "--orca-font"
-];
-
-// Read the contract off this page as it is rendering right now, so the frame always opens in the
-// live theme rather than whatever the app started in.
 function OrcaThemeSnapshot() {
-  const style = getComputedStyle(document.documentElement);
+  const style = document.getElementById("orca-host-theme-vars");
-  const vars = {};
-  ORCA_THEME_VARS.forEach((name) => {
-    // Values are host-produced colors and a pre-sanitized font stack; strip anything that could end
-    // the declaration or the <style> block it gets inlined into.
-    const value = String(style.getPropertyValue(name) || "").trim().replace(/[<>{};]/g, "");
-    if (value)
-      vars[name] = value;
-  });
   return {
     theme: document.documentElement.getAttribute("data-orca-theme") === "dark" ? "dark" : "light",
-    vars: vars
+    css: style ? style.textContent : ""
   };
 }
 
 // Inlined into a <script> or a JSON payload: a stored "</script>" would close the tag early, so
 // escape "<" — the literal stays valid JSON.
 function OrcaInlineJson(value) {
-  return JSON.stringify(value === undefined ? null : value).replace(/</g, "\\u003c");
+  return JSON.stringify(value).replace(/</g, "\\u003c");
 }
 
 // What a custom UI can learn about the surface it is being edited on. Kept to what changes the
@@ -66,13 +50,9 @@ function BuildCustomConfigDocument(html, config, context) {
   var theme = ${OrcaInlineJson(theme)};
 
   function applyTheme(next) {
-    if (next && next.vars) theme = next;
+    if (next && typeof next.css === "string") theme = next;
-    var css = ":root{";
-    for (var name in theme.vars)
-      if (Object.prototype.hasOwnProperty.call(theme.vars, name)) css += name + ":" + theme.vars[name] + ";";
-    css += "color-scheme:" + theme.theme + ";}";
     var style = document.getElementById("orca-host-theme-vars");
-    if (style) style.textContent = css;
+    if (style) style.textContent = theme.css;
     if (document.documentElement) document.documentElement.setAttribute("data-orca-theme", theme.theme);
     themeHandlers.forEach(function (handler) {
       try { handler(theme.theme); } catch (e) {}
@@ -116,9 +96,9 @@ function BuildCustomConfigDocument(html, config, context) {
 // The host re-themes an open dialog in place (WebViewHostDialog::host_theme_apply_js rewrites the
 // injected variables and re-stamps data-orca-theme), which a sandboxed child frame never sees. Relay
 // it so a custom UI follows a light/dark switch without being reopened.
-function OrcaWatchThemeForFrame(getFrame) {
+function OrcaWatchThemeForFrame(frameId) {
   const relay = () => {
-    const frame = getFrame();
+    const frame = document.getElementById(frameId);
     if (!frame || frame.hidden || !frame.contentWindow)
       return;
     frame.contentWindow.postMessage({ __orca: "theme", theme: OrcaThemeSnapshot() }, "*");

sandboxes/orca_twistify_plugin_example_any.py

@@ -490,6 +490,8 @@ _CONFIG_UI = """
     draw();
     restoreReadout();
     refreshState();
+    labelRestore();
+    setInputsEnabled(!context.readOnly);
   }
 
   // "Restore defaults" writes the plugin's own defaults globally, but in a preset it discards that
@@ -513,8 +515,6 @@ _CONFIG_UI = """
 
   buildRows();
   load(window.orca ? window.orca.getConfig() : {});
-  labelRestore();
-  setInputsEnabled(!context.readOnly);
 
   document.getElementById("save").addEventListener("click", function () {
     if (!window.orca) return;
@@ -532,8 +532,6 @@ _CONFIG_UI = """
       if (first) { first = false; return; }
       if (window.orca.getContext) context = window.orca.getContext();
       load(config);
-      labelRestore();
-      setInputsEnabled(!context.readOnly);
       announce("Saved");
     });
   }

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 +407,12 @@ public:
     // Printer machine limits, those are contained in printer_options().
     static const std::vector<std::string>&  machine_limits_options();
 
+    // The option key holding this preset type's plugin capability overrides. The print, printer and
+    // filament presets each keep their own key so the values never clobber one another when the
+    // presets merge into a single full config; print doubles as the fallback for other types, which
+    // have 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 +1081,23 @@ void PrintConfigDef::init_common_params()
         def->set_default_value(new ConfigOptionString());
     }
 
-    def = this->add("plugin_config_overrides", coString);
+    // Per preset type (Preset::plugin_overrides_key): the print, printer and filament presets each hold
-    def->label = L("Capabilities");
+    // the capability overrides for their own plugin-backed options (slicing_pipeline_plugin,
-    def->tooltip = L("Configuration for the plugin capabilities this preset uses, overriding the global "
+    // printer_agent, ...). Separate keys keep them from clobbering each other when the presets merge
-                     "Capabilities configuration. Stored as a raw JSON array and edited through the dialog "
+    // into one full config. They replace a single shared "plugin_config_overrides" deliberately without
-                     "behind the button, never typed in directly.");
+    // handle_legacy migration: that key existed in nightly builds only, never in a release. Never shown
-    // Never shown as a text field: GUIType::plugin_config renders a button that opens PluginsConfigDialog.
+    // as a text field: GUIType::plugin_config renders a button that opens PluginsConfigDialog.
-    def->gui_type = ConfigOptionDef::GUIType::plugin_config;
+    for (const char* key : {"print_plugin_config_overrides", "printer_plugin_config_overrides", "filament_plugin_config_overrides"}) {
-    def->mode = comAdvanced;
+        def = this->add(key, coString);
-    def->cli = ConfigOptionDef::nocli;
+        def->label = L("Capabilities");
-    def->set_default_value(new ConfigOptionString(""));
+        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/libslic3r/PrintObject.cpp

@@ -1254,8 +1254,7 @@ bool PrintObject::invalidate_state_by_config_options(
             || opt_key == "interlocking_beam_layer_count"
             || opt_key == "interlocking_depth"
             || opt_key == "interlocking_boundary_avoidance"
-            || opt_key == "interlocking_beam_width"
+            || opt_key == "interlocking_beam_width") {
-            || opt_key == "plugin_config_overrides") {
             steps.emplace_back(posSlice);
 		} else if (
                opt_key == "elefant_foot_compensation"

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)) {
+        const std::string overrides_key = Preset::plugin_overrides_key(m_type);
-            if (Field* overrides_field = get_field(PLUGIN_OVERRIDES_OPTION_KEY))
+        if (prune_stale_plugin_overrides(*m_config, overrides_key)) {
-                overrides_field->set_value(boost::any(m_config->opt_string(PLUGIN_OVERRIDES_OPTION_KEY)), false);
+            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;
-
+            for (const auto& [options, edited] : scopes)
-            const auto& print_options = Preset::print_options();
+                if (contains(*options, key)) {
-            if (std::find(print_options.begin(), print_options.end(), key) != print_options.end()) {
+                    preset = edited;
-                preset = &bundle->prints.get_edited_preset();
+                    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 +49,16 @@ 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
+// Drops plugin override entries for capabilities no longer named by any plugin-backed option's current
-// option's current value in `config` (e.g. slicing_pipeline_plugin cleared or switched to a
+// value in `config` (e.g. slicing_pipeline_plugin cleared or switched to a different capability), and
-// different capability), and writes the result back if anything changed. Called wherever a
+// writes the result back to `overrides_key` if anything changed. Called wherever a plugin-backed
-// plugin-backed option's value changes, so a saved preset never carries configuration for a
+// option's value changes, so a saved preset never carries configuration for a capability it no longer
-// capability it no longer references. Returns true if `config` was modified, so a caller holding a
+// references. Returns true if `config` was modified, so a caller holding a GUI field over
-// GUI field over PLUGIN_OVERRIDES_OPTION_KEY knows it must refresh that field's displayed value.
+// `overrides_key` knows it must refresh that field's displayed value.
-bool prune_stale_plugin_overrides(DynamicConfig& config);
+bool prune_stale_plugin_overrides(DynamicConfig& config, const std::string& overrides_key);
 
 struct EffectiveCapabilityConfig
 {

tests/fff_print/test_slicing_pipeline_hook.cpp

@@ -218,6 +218,20 @@ TEST_CASE("Changing slicing_pipeline_plugin invalidates posSlice", "[slicing_pip
     CHECK_FALSE(print.objects().front()->is_step_done(posSlice)); // re-slice required
 }
 
+// Editing a slicing plugin's config (print_plugin_config_overrides) must re-run posSlice, where the
+// plugin transforms each layer's geometry; otherwise the cached slice keeps the old config's result.
+TEST_CASE("Changing print_plugin_config_overrides invalidates posSlice", "[slicing_pipeline]") {
+    Slic3r::Print print; Slic3r::Model model;
+    auto config = Slic3r::DynamicPrintConfig::full_print_config();
+    init_print({cube(20)}, print, model, config);
+    print.process();
+    REQUIRE(print.objects().front()->is_step_done(posSlice));
+    config.set_key_value("print_plugin_config_overrides",
+        new Slic3r::ConfigOptionString("[{\"type\":\"slicing-pipeline\",\"name\":\"Twistify\",\"config\":{\"twist_deg_per_mm\":2.0}}]"));
+    print.apply(model, config);
+    CHECK_FALSE(print.objects().front()->is_step_done(posSlice)); // re-slice required
+}
+
 #include <catch2/matchers/catch_matchers_floating_point.hpp>
 
 // A similarity transform (rotate + uniform scale) applied to slices at Step.posSlice, matching

tests/libslic3r/test_preset_bundle_loading.cpp

@@ -464,3 +464,29 @@ TEST_CASE("Profile validator flags dangling and renamed preset references", "[Pr
     }
 }
 
+// Each preset type stores its plugin capability overrides under its own option key. Merging the print,
+// printer and filament presets into one full config under a shared key would let the last preset applied
+// overwrite the others' overrides -- the clobber that stopped an edited slicing-pipeline (print) override
+// from reaching Print::apply's diff, so re-configuring a plugin never re-sliced. Distinct per-type keys
+// make that collision impossible; guard the scoping here.
+TEST_CASE("Plugin capability override keys are scoped per preset type", "[Preset][Plugin]")
+{
+    // Pin the key names: presets and 3mf files store them verbatim, so a rename is a format change.
+    CHECK(Preset::plugin_overrides_key(Preset::TYPE_PRINT)    == std::string("print_plugin_config_overrides"));
+    CHECK(Preset::plugin_overrides_key(Preset::TYPE_PRINTER)  == std::string("printer_plugin_config_overrides"));
+    CHECK(Preset::plugin_overrides_key(Preset::TYPE_FILAMENT) == std::string("filament_plugin_config_overrides"));
+
+    // ...and each key lives on exactly its own preset type's option list, so no two ever share a slot.
+    const std::pair<Preset::Type, const std::vector<std::string>*> scopes[] = {
+        {Preset::TYPE_PRINT,    &Preset::print_options()},
+        {Preset::TYPE_PRINTER,  &Preset::printer_options()},
+        {Preset::TYPE_FILAMENT, &Preset::filament_options()},
+    };
+    for (const auto &owner : scopes)
+        for (const auto &scoped : scopes) {
+            const std::string key = Preset::plugin_overrides_key(scoped.first);
+            CAPTURE(owner.first, key);
+            CHECK(contains(*owner.second, key) == (owner.first == scoped.first));
+        }
+}
+