diff --git a/toonz/sources/toonzqt/pluginhost.cpp b/toonz/sources/toonzqt/pluginhost.cpp
index efbd37b9..e4d664ce 100644
--- a/toonz/sources/toonzqt/pluginhost.cpp
+++ b/toonz/sources/toonzqt/pluginhost.cpp
@@ -445,12 +445,12 @@ TFx *RasterFxPluginHost::clone(bool recursive) const
 		}
 	}
 
-	printf("recursive:%d params:%d\n", recursive, pi_->params_.size());
+	printf("recursive:%d params:%d\n", recursive, params_.size());
 	// clone params before TFx::clone().
 	/* ui_pages_, param_views_ は pi に移ったが createParam の呼び出しだけはしておかないと Fx Settings 構築時に assert failed になる */
-	for (auto const &param : pi_->params_) {
+	for (auto const &param : params_) {
 		/* 古い createParam() は desc をとらず、コンストラクト時にデフォルト値を持つタイプの T*Param を再作成できない */
-		plugin->createParam(param->desc(), true);
+		plugin->createParam(param->desc());
 	}
 
 	return TFx::clone(plugin, recursive);
@@ -606,17 +606,17 @@ UIPage *RasterFxPluginHost::createUIPage(const char *name)
 }
 
 // deprecated. for migration.
-Param *RasterFxPluginHost::createParam(const char *name, toonz_param_type_enum e, bool fromclone)
+Param *RasterFxPluginHost::createParam(const char *name, toonz_param_type_enum e)
 {
 	toonz_param_desc_t *desc = new toonz_param_desc_t;
 	memset(desc, 0, sizeof(toonz_param_desc_t));
 	desc->base.ver = {1, 0};
 	desc->key = name;
 	desc->traits_tag = e;
-	return createParam(desc, fromclone);
+	return createParam(desc);
 }
 
-Param *RasterFxPluginHost::createParam(const toonz_param_desc_t *desc, bool fromclone)
+Param *RasterFxPluginHost::createParam(const toonz_param_desc_t *desc)
 {
 	TParamP p = parameter_factory(desc);
 	if (!p)
@@ -627,31 +627,15 @@ Param *RasterFxPluginHost::createParam(const toonz_param_desc_t *desc, bool from
 
 	bindParam(this, desc->key, p);
 
-	/* pi は永続性があるので clone から呼ばれた場合は書き換えない */
-	if (!fromclone) {
-		// add to a map
-		Param *param = nullptr;
-		for (auto const &p : pi_->params_) {
-			if (p->name() == desc->key) {
-				param = p;
-				break;
-			}
-		}
-		if (!param) {
-			pi_->params_.push_back(nullptr);
-			pi_->params_.back() = new Param(this, desc->key, toonz_param_type_enum(desc->traits_tag), desc);
-			param = pi_->params_.back();
-		}
-		return param;
-	}
-	return nullptr;
+	params_.push_back(std::make_shared<Param>(this, desc->key, toonz_param_type_enum(desc->traits_tag), desc));
+	return params_.back().get();
 }
 
 Param *RasterFxPluginHost::getParam(const char *name) const
 {
-	for (auto &param : pi_->params_) {
+	for (auto &param : params_) {
 		if (param->name() == name) {
-			return param;
+			return param.get();
 		}
 	}
 	return nullptr;
@@ -795,7 +779,7 @@ bool RasterFxPluginHost::setParamStructure(int n, toonz_param_page_t *p, int &er
 					else {
 						if (!validateKeyName(desc->key))
 							err |= TOONZ_PARAM_ERROR_KEY_NAME;
-						for (auto it : pi_->params_) {
+						for (auto it : params_) {
 							if (it->name() == desc->key) {
 								err |= TOONZ_PARAM_ERROR_KEY_DUP;
 								break;
diff --git a/toonz/sources/toonzqt/pluginhost.h b/toonz/sources/toonzqt/pluginhost.h
index c22d599d..ccbdab9b 100644
--- a/toonz/sources/toonzqt/pluginhost.h
+++ b/toonz/sources/toonzqt/pluginhost.h
@@ -89,7 +89,6 @@ public:
 	toonz_param_page_t *param_pages_;
 
 	std::vector<UIPage *> ui_pages_;
-	std::vector<Param *> params_;
 	std::vector<ParamView *> param_views_;
 	std::map<std::string, port_description_t> port_mapper_;
 
@@ -146,6 +145,7 @@ class RasterFxPluginHost : public TZeraryFx, public TPluginInterface
 	PluginInformation *pi_;
 
 	std::vector<std::shared_ptr<TFxPort>> inputs_;
+	std::vector<std::shared_ptr<Param>> params_;
 	void *user_data_;
 
 	static bool validateKeyName(const char *name);
@@ -180,8 +180,8 @@ public:
 	bool setParamStructure(int n, toonz_param_page_t *descs, int &err, void *&pos);
 	bool addPortDesc(port_description_t &&);
 
-	Param *createParam(const toonz_param_desc_t *, bool fromclone = false);
-	Param *createParam(const char *name, toonz_param_type_enum e, bool fromclone = false);
+	Param *createParam(const toonz_param_desc_t *);
+	Param *createParam(const char *name, toonz_param_type_enum e);
 	Param *getParam(const char *name) const;
 	ParamView *createParamView();