diff --git a/src/ecmascript/quickjs.h b/src/ecmascript/quickjs.h
index a10115a4..8c806fe8 100644
--- a/src/ecmascript/quickjs.h
+++ b/src/ecmascript/quickjs.h
@@ -3,6 +3,18 @@
 
 #include <quickjs/quickjs.h>
 
+#ifdef ECMASCRIPT_DEBUG
+
+#define RETURN_JS(obj) \
+	fprintf(stderr, "%s:%d obj=%p\n", __FILE__, __LINE__, JS_VALUE_GET_PTR(obj)); \
+	return obj
+
+#else
+
+#define RETURN_JS(obj) return obj
+
+#endif
+
 struct ecmascript_interpreter;
 struct form_view;
 struct form_state;
diff --git a/src/ecmascript/quickjs/attr.c b/src/ecmascript/quickjs/attr.c
index 779f9042..fd427dce 100644
--- a/src/ecmascript/quickjs/attr.c
+++ b/src/ecmascript/quickjs/attr.c
@@ -20,6 +20,7 @@
 #include "document/forms.h"
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/attr.h"
 #include "intl/libintl.h"
 #include "main/select.h"
@@ -79,7 +80,9 @@ js_attr_get_property_name(JSContext *ctx, JSValueConst this_val)
 
 	xmlpp::ustring v = attr->get_name();
 
-	return JS_NewString(ctx, v.c_str());
+	JSValue r = JS_NewString(ctx, v.c_str());
+
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -106,7 +109,9 @@ js_attr_get_property_value(JSContext *ctx, JSValueConst this_val)
 
 	xmlpp::ustring v = attr->get_value();
 
-	return JS_NewString(ctx, v.c_str());
+	JSValue r = JS_NewString(ctx, v.c_str());
+
+	RETURN_JS(r);
 }
 
 static const JSCFunctionListEntry js_attr_proto_funcs[] = {
@@ -136,7 +141,7 @@ js_attr_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst *ar
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -175,5 +180,5 @@ getAttr(JSContext *ctx, void *node)
 
 	JS_SetOpaque(attr_obj, node);
 
-	return attr_obj;
+	RETURN_JS(attr_obj);
 }
diff --git a/src/ecmascript/quickjs/attributes.c b/src/ecmascript/quickjs/attributes.c
index 02676a76..029f55d4 100644
--- a/src/ecmascript/quickjs/attributes.c
+++ b/src/ecmascript/quickjs/attributes.c
@@ -20,6 +20,7 @@
 #include "document/forms.h"
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/attr.h"
 #include "ecmascript/quickjs/attributes.h"
 #include "intl/libintl.h"
@@ -190,7 +191,7 @@ js_attributes_namedItem2(JSContext *ctx, JSValueConst this_val, const char *str)
 
 		if (name == attr->get_name()) {
 			JSValue obj = getAttr(ctx, attr);
-			return obj;
+			RETURN_JS(obj);
 		}
 	}
 
@@ -219,7 +220,7 @@ js_attributes_getNamedItem(JSContext *ctx, JSValueConst this_val, int argc, JSVa
 	JSValue ret = js_attributes_namedItem2(ctx, this_val, str);
 	JS_FreeCString(ctx, str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static const JSCFunctionListEntry js_attributes_proto_funcs[] = {
@@ -250,7 +251,7 @@ js_attributes_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueCon
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -290,5 +291,5 @@ getAttributes(JSContext *ctx, void *node)
 	JS_SetOpaque(attributes_obj, node);
 	js_attributes_set_items(ctx, attributes_obj, node);
 
-	return attributes_obj;
+	RETURN_JS(attributes_obj);
 }
diff --git a/src/ecmascript/quickjs/collection.c b/src/ecmascript/quickjs/collection.c
index e4d2856d..04293bf0 100644
--- a/src/ecmascript/quickjs/collection.c
+++ b/src/ecmascript/quickjs/collection.c
@@ -187,7 +187,7 @@ js_htmlCollection_namedItem(JSContext *ctx, JSValueConst this_val, int argc, JSV
 	JSValue ret = js_htmlCollection_namedItem2(ctx, this_val, str);
 	JS_FreeCString(ctx, str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static void
@@ -269,7 +269,7 @@ js_htmlCollection_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValu
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -308,7 +308,8 @@ getCollection(JSContext *ctx, void *node)
 	auto node_find = map_collections.find(node);
 
 	if (node_find != map_collections.end()) {
-		return JS_DupValue(ctx, node_find->second);
+		JSValue r = JS_DupValue(ctx, node_find->second);
+		RETURN_JS(r);
 	}
 	JSValue htmlCollection_obj = JS_NewArray(ctx);
 	JS_SetPropertyFunctionList(ctx, htmlCollection_obj, js_htmlCollection_proto_funcs, countof(js_htmlCollection_proto_funcs));
@@ -317,5 +318,6 @@ getCollection(JSContext *ctx, void *node)
 	js_htmlCollection_set_items(ctx, htmlCollection_obj, node);
 	map_collections[node] = htmlCollection_obj;
 
-	return JS_DupValue(ctx, htmlCollection_obj);
+	JSValue rr = JS_DupValue(ctx, htmlCollection_obj);
+	RETURN_JS(rr);
 }
diff --git a/src/ecmascript/quickjs/console.c b/src/ecmascript/quickjs/console.c
index 7192560c..a41a1110 100644
--- a/src/ecmascript/quickjs/console.c
+++ b/src/ecmascript/quickjs/console.c
@@ -16,6 +16,7 @@
 #include "dialogs/menu.h"
 #include "dialogs/status.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/console.h"
 #include "intl/libintl.h"
 #include "osdep/newwin.h"
@@ -113,7 +114,7 @@ js_console_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
diff --git a/src/ecmascript/quickjs/document.c b/src/ecmascript/quickjs/document.c
index 84003f51..06f8b998 100644
--- a/src/ecmascript/quickjs/document.c
+++ b/src/ecmascript/quickjs/document.c
@@ -134,7 +134,7 @@ js_document_get_property_baseURI(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewString(ctx, str);
 	mem_free(str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -206,9 +206,11 @@ js_document_get_property_cookie(JSContext *ctx, JSValueConst this_val)
 		strncpy(cookiestr, cookies->source, 1023);
 		done_string(cookies);
 
-		return JS_NewString(ctx, cookiestr);
+		JSValue r = JS_NewString(ctx, cookiestr);
+		RETURN_JS(r);
 	} else {
-		return JS_NewStringLen(ctx, "", 0);
+		JSValue rr = JS_NewStringLen(ctx, "", 0);
+		RETURN_JS(rr);
 	}
 }
 
@@ -269,7 +271,8 @@ js_document_get_property_charset(JSContext *ctx, JSValueConst this_val, JSValue
 		encoding = "utf-8";
 	}
 
-	return JS_NewStringLen(ctx, encoding.c_str(), encoding.length());
+	JSValue r = JS_NewStringLen(ctx, encoding.c_str(), encoding.length());
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -406,7 +409,7 @@ js_document_get_property_documentURI(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewString(ctx, str);
 	mem_free(str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -438,7 +441,7 @@ js_document_get_property_domain(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewString(ctx, str);
 	mem_free(str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -613,7 +616,7 @@ js_document_get_property_location(JSContext *ctx, JSValueConst this_val)
 #endif
 	struct ecmascript_interpreter *interpreter = JS_GetContextOpaque(ctx);
 
-	return interpreter->location_obj;
+	RETURN_JS(interpreter->location_obj);
 }
 
 static JSValue
@@ -698,7 +701,7 @@ js_document_get_property_referrer(JSContext *ctx, JSValueConst this_val)
 				JSValue ret = JS_NewString(ctx, str);
 				mem_free(str);
 
-				return ret;
+				RETURN_JS(ret);
 			} else {
 				return JS_UNDEFINED;
 			}
@@ -712,7 +715,7 @@ js_document_get_property_referrer(JSContext *ctx, JSValueConst this_val)
 			JSValue ret = JS_NewString(ctx, str);
 			mem_free(str);
 
-			return ret;
+			RETURN_JS(ret);
 		} else {
 			return JS_UNDEFINED;
 		}
@@ -780,7 +783,8 @@ js_document_get_property_title(JSContext *ctx, JSValueConst this_val)
 	}
 	doc_view = vs->doc_view;
 	document = doc_view->document;
-	return JS_NewString(ctx, document->title);
+	JSValue r = JS_NewString(ctx, document->title);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -848,7 +852,7 @@ js_document_get_property_url(JSContext *ctx, JSValueConst this_val)
 		JSValue ret = JS_NewString(ctx, str);
 		mem_free(str);
 
-		return ret;
+		RETURN_JS(ret);
 	} else {
 		return JS_UNDEFINED;
 	}
@@ -1554,7 +1558,8 @@ js_doctype_get_property_publicId(JSContext *ctx, JSValueConst this_val)
 	}
 	xmlpp::ustring v = dtd->get_external_id();
 
-	return JS_NewStringLen(ctx, v.c_str(), v.length());
+	JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -1571,7 +1576,8 @@ js_doctype_get_property_systemId(JSContext *ctx, JSValueConst this_val)
 	}
 	xmlpp::ustring v = dtd->get_system_id();
 
-	return JS_NewStringLen(ctx, v.c_str(), v.length());
+	JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+	RETURN_JS(r);
 }
 
 static const JSCFunctionListEntry js_document_proto_funcs[] = {
@@ -1638,7 +1644,7 @@ js_document_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -1664,7 +1670,7 @@ js_document_init(JSContext *ctx, JSValue global_obj)
 
 	JS_SetPropertyStr(ctx, global_obj, "document", document_proto);
 
-	return document_proto;
+	RETURN_JS(document_proto);
 }
 
 static const JSCFunctionListEntry js_doctype_proto_funcs[] = {
@@ -1706,7 +1712,7 @@ js_doctype_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -1751,7 +1757,8 @@ getDoctype(JSContext *ctx, void *node)
 	auto node_find = map_doctypes.find(node);
 
 	if (node_find != map_doctypes.end()) {
-		return JS_DupValue(ctx, node_find->second);
+		JSValue r = JS_DupValue(ctx, node_find->second);
+		RETURN_JS(r);
 	}
 	JSValue doctype_obj = JS_NewObjectClass(ctx, js_doctype_class_id);
 	JS_SetPropertyFunctionList(ctx, doctype_obj, js_doctype_proto_funcs, countof(js_doctype_proto_funcs));
@@ -1760,7 +1767,8 @@ getDoctype(JSContext *ctx, void *node)
 
 	map_doctypes[node] = doctype_obj;
 
-	return JS_DupValue(ctx, doctype_obj);
+	JSValue rr = JS_DupValue(ctx, doctype_obj);
+	RETURN_JS(rr);
 }
 
 JSValue
@@ -1776,5 +1784,5 @@ getDocument(JSContext *ctx, void *doc)
 	JS_SetClassProto(ctx, js_document_class_id, document_obj);
 	JS_SetOpaque(document_obj, doc);
 
-	return document_obj;
+	RETURN_JS(document_obj);
 }
diff --git a/src/ecmascript/quickjs/element.c b/src/ecmascript/quickjs/element.c
index 07e7d280..e4aa287a 100644
--- a/src/ecmascript/quickjs/element.c
+++ b/src/ecmascript/quickjs/element.c
@@ -21,6 +21,7 @@
 #include "document/view.h"
 #include "ecmascript/css2xpath.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/attr.h"
 #include "ecmascript/quickjs/attributes.h"
 #include "ecmascript/quickjs/collection.h"
@@ -184,7 +185,8 @@ js_element_get_property_className(JSContext *ctx, JSValueConst this_val)
 	}
 	xmlpp::ustring v = el->get_attribute_value("class");
 
-	return JS_NewStringLen(ctx, v.c_str(), v.length());
+	JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -204,7 +206,8 @@ js_element_get_property_dir(JSContext *ctx, JSValueConst this_val)
 	if (v != "auto" && v != "ltr" && v != "rtl") {
 		v = "";
 	}
-	return JS_NewStringLen(ctx, v.c_str(), v.length());
+	JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -271,7 +274,8 @@ js_element_get_property_id(JSContext *ctx, JSValueConst this_val)
 	}
 	xmlpp::ustring v = el->get_attribute_value("id");
 
-	return JS_NewStringLen(ctx, v.c_str(), v.length());
+	JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -287,7 +291,8 @@ js_element_get_property_lang(JSContext *ctx, JSValueConst this_val)
 	}
 	xmlpp::ustring v = el->get_attribute_value("lang");
 
-	return JS_NewStringLen(ctx, v.c_str(), v.length());
+	JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -381,7 +386,8 @@ js_element_get_property_nodeName(JSContext *ctx, JSValueConst this_val)
 	xmlpp::ustring v;
 
 	if (!node) {
-		return JS_NewStringLen(ctx, "", 0);
+		JSValue r = JS_NewStringLen(ctx, "", 0);
+		RETURN_JS(r);
 	}
 	auto el = dynamic_cast<const xmlpp::Element*>(node);
 
@@ -399,7 +405,8 @@ js_element_get_property_nodeName(JSContext *ctx, JSValueConst this_val)
 		}
 	}
 
-	return JS_NewStringLen(ctx, v.c_str(), v.length());
+	JSValue rr = JS_NewStringLen(ctx, v.c_str(), v.length());
+	RETURN_JS(rr);
 }
 
 static JSValue
@@ -449,7 +456,8 @@ js_element_get_property_nodeValue(JSContext *ctx, JSValueConst this_val)
 	if (el) {
 		xmlpp::ustring v = el->get_value();
 
-		return JS_NewStringLen(ctx, v.c_str(), v.length());
+		JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+		RETURN_JS(r);
 	}
 
 	auto el2 = dynamic_cast<const xmlpp::TextNode*>(node);
@@ -457,7 +465,8 @@ js_element_get_property_nodeValue(JSContext *ctx, JSValueConst this_val)
 	if (el2) {
 		xmlpp::ustring v = el2->get_content();
 
-		return JS_NewStringLen(ctx, v.c_str(), v.length());
+		JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+		RETURN_JS(r);
 	}
 
 	auto el3 = dynamic_cast<const xmlpp::CommentNode*>(node);
@@ -465,7 +474,8 @@ js_element_get_property_nodeValue(JSContext *ctx, JSValueConst this_val)
 	if (el3) {
 		xmlpp::ustring v = el3->get_content();
 
-		return JS_NewStringLen(ctx, v.c_str(), v.length());
+		JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+		RETURN_JS(r);
 	}
 
 	return JS_UNDEFINED;
@@ -500,7 +510,8 @@ js_element_get_property_ownerDocument(JSContext *ctx, JSValueConst this_val)
 #endif
 	struct ecmascript_interpreter *interpreter = JS_GetContextOpaque(ctx);
 
-	return JS_DupValue(ctx, interpreter->document_obj);
+	JSValue r = JS_DupValue(ctx, interpreter->document_obj);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -607,7 +618,8 @@ js_element_get_property_tagName(JSContext *ctx, JSValueConst this_val)
 	xmlpp::ustring v = el->get_name();
 	std::transform(v.begin(), v.end(), v.begin(), ::toupper);
 
-	return JS_NewStringLen(ctx, v.c_str(), v.length());
+	JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -623,7 +635,8 @@ js_element_get_property_title(JSContext *ctx, JSValueConst this_val)
 	}
 	xmlpp::ustring v = el->get_attribute_value("title");
 
-	return JS_NewStringLen(ctx, v.c_str(), v.length());
+	JSValue r = JS_NewStringLen(ctx, v.c_str(), v.length());
+	RETURN_JS(r);
 }
 
 static int was_el = 0;
@@ -728,7 +741,7 @@ js_element_get_property_innerHtml(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewStringLen(ctx, buf.source, buf.length);
 	done_string(&buf);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -748,7 +761,7 @@ js_element_get_property_outerHtml(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewStringLen(ctx, buf.source, buf.length);
 	done_string(&buf);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -768,7 +781,7 @@ js_element_get_property_textContent(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewStringLen(ctx, buf.source, buf.length);
 	done_string(&buf);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -1177,7 +1190,8 @@ js_element_getAttribute(JSContext *ctx, JSValueConst this_val, int argc, JSValue
 	}
 	xmlpp::ustring val = attr->get_value();
 
-	return JS_NewStringLen(ctx, val.c_str(), val.length());
+	JSValue r = JS_NewStringLen(ctx, val.c_str(), val.length());
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -1645,7 +1659,7 @@ js_element_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -1691,7 +1705,8 @@ getElement(JSContext *ctx, void *node)
 	auto node_find = map_elements.find(node);
 
 	if (node_find != map_elements.end()) {
-		return JS_DupValue(ctx, node_find->second);
+		JSValue r = JS_DupValue(ctx, node_find->second);
+		RETURN_JS(r);
 	}
 
 	JSValue element_obj = JS_NewObjectClass(ctx, js_element_class_id);
@@ -1702,5 +1717,6 @@ getElement(JSContext *ctx, void *node)
 
 	map_elements[node] = element_obj;
 
-	return JS_DupValue(ctx, element_obj);
+	JSValue rr = JS_DupValue(ctx, element_obj);
+	RETURN_JS(rr);
 }
diff --git a/src/ecmascript/quickjs/form.c b/src/ecmascript/quickjs/form.c
index 79810b64..40d49a0e 100644
--- a/src/ecmascript/quickjs/form.c
+++ b/src/ecmascript/quickjs/form.c
@@ -377,7 +377,7 @@ js_form_elements_namedItem(JSContext *ctx, JSValueConst this_val, int argc, JSVa
 	JSValue ret = js_form_elements_namedItem2(ctx, this_val, str);
 	JS_FreeCString(ctx, str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 static struct form_view *
 js_form_get_form_view(JSContext *ctx, JSValueConst this_val, JSValueConst *argv)
@@ -413,7 +413,8 @@ js_form_get_property_action(JSContext *ctx, JSValueConst this_val)
 	form = form_GetOpaque(this_val);
 	assert(form);
 
-	return JS_NewString(ctx, form->action);
+	JSValue r = JS_NewString(ctx, form->action);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -508,7 +509,8 @@ getFormElements(JSContext *ctx, struct form_view *fv)
 	auto node_find = map_form_elements.find(fv);
 
 	if (node_find != map_form_elements.end()) {
-		return JS_DupValue(ctx, node_find->second);
+		JSValue r = JS_DupValue(ctx, node_find->second);
+		RETURN_JS(r);
 	}
 	JSValue form_elements_obj = JS_NewArray(ctx);
 
@@ -518,7 +520,8 @@ getFormElements(JSContext *ctx, struct form_view *fv)
 	js_form_set_items(ctx, form_elements_obj, fv);
 	map_form_elements[fv] = form_elements_obj;
 
-	return JS_DupValue(ctx, form_elements_obj);
+	JSValue rr = JS_DupValue(ctx, form_elements_obj);
+	RETURN_JS(rr);
 }
 
 static JSValue
@@ -562,14 +565,19 @@ js_form_get_property_encoding(JSContext *ctx, JSValueConst this_val)
 	form = form_GetOpaque(this_val);
 	assert(form);
 
+	JSValue r;
+
 	switch (form->method) {
 	case FORM_METHOD_GET:
 	case FORM_METHOD_POST:
-		return JS_NewString(ctx, "application/x-www-form-urlencoded");
+		r = JS_NewString(ctx, "application/x-www-form-urlencoded");
+		RETURN_JS(r);
 	case FORM_METHOD_POST_MP:
-		return JS_NewString(ctx, "multipart/form-data");
+		r = JS_NewString(ctx, "multipart/form-data");
+		RETURN_JS(r);
 	case FORM_METHOD_POST_TEXT_PLAIN:
-		return JS_NewString(ctx, "text/plain");
+		r = JS_NewString(ctx, "text/plain");
+		RETURN_JS(r);
 	}
 
 	return JS_UNDEFINED;
@@ -668,14 +676,18 @@ js_form_get_property_method(JSContext *ctx, JSValueConst this_val)
 	form = form_GetOpaque(this_val);
 	assert(form);
 
+	JSValue r;
+
 	switch (form->method) {
 	case FORM_METHOD_GET:
-		return JS_NewStringLen(ctx, "GET", 3);
+		r = JS_NewStringLen(ctx, "GET", 3);
+		RETURN_JS(r);
 
 	case FORM_METHOD_POST:
 	case FORM_METHOD_POST_MP:
 	case FORM_METHOD_POST_TEXT_PLAIN:
-		return JS_NewStringLen(ctx, "POST", 4);
+		r = JS_NewStringLen(ctx, "POST", 4);
+		RETURN_JS(r);
 	}
 
 	return JS_UNDEFINED;
@@ -747,7 +759,8 @@ js_form_get_property_name(JSContext *ctx, JSValueConst this_val)
 	form = form_GetOpaque(this_val);
 	assert(form);
 
-	return JS_NewString(ctx, form->name);
+	JSValue r = JS_NewString(ctx, form->name);
+	RETURN_JS(r);
 }
 
 /* @form_class.setProperty */
@@ -811,7 +824,8 @@ js_form_get_property_target(JSContext *ctx, JSValueConst this_val)
 	form = form_GetOpaque(this_val);
 	assert(form);
 
-	return JS_NewString(ctx, form->target);
+	JSValue r = JS_NewString(ctx, form->target);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -926,7 +940,7 @@ js_elements_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -1002,7 +1016,7 @@ js_form_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst *ar
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -1040,7 +1054,8 @@ getForm(JSContext *ctx, struct form *form)
 	auto node_find = map_form.find(form);
 
 	if (node_find != map_form.end()) {
-		return JS_DupValue(ctx, node_find->second);
+		JSValue r = JS_DupValue(ctx, node_find->second);
+		RETURN_JS(r);
 	}
 	JSValue form_obj = JS_NewArray(ctx);
 
@@ -1051,5 +1066,6 @@ getForm(JSContext *ctx, struct form *form)
 
 	map_form[form] = form_obj;
 
-	return JS_DupValue(ctx, form_obj);
+	JSValue rr = JS_DupValue(ctx, form_obj);
+	RETURN_JS(rr);
 }
diff --git a/src/ecmascript/quickjs/forms.c b/src/ecmascript/quickjs/forms.c
index 996a09ac..d22bacb8 100644
--- a/src/ecmascript/quickjs/forms.c
+++ b/src/ecmascript/quickjs/forms.c
@@ -217,7 +217,7 @@ js_forms_namedItem(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst
 	JSValue ret = js_find_form_by_name(ctx, doc_view, str);
 	JS_FreeCString(ctx, str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 #if 0
@@ -323,7 +323,7 @@ js_forms_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst *a
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -361,7 +361,8 @@ getForms(JSContext *ctx, void *node)
 	auto node_find = map_forms.find(node);
 
 	if (node_find != map_forms.end()) {
-		return JS_DupValue(ctx, node_find->second);
+		JSValue r = JS_DupValue(ctx, node_find->second);
+		RETURN_JS(r);
 	}
 	JSValue forms_obj = JS_NewArray(ctx);
 	JS_SetPropertyFunctionList(ctx, forms_obj, js_forms_proto_funcs, countof(js_forms_proto_funcs));
@@ -369,5 +370,6 @@ getForms(JSContext *ctx, void *node)
 	js_forms_set_items(ctx, forms_obj, node);
 	map_forms[node] = forms_obj;
 
-	return JS_DupValue(ctx, forms_obj);
+	JSValue rr = JS_DupValue(ctx, forms_obj);
+	RETURN_JS(rr);
 }
diff --git a/src/ecmascript/quickjs/history.c b/src/ecmascript/quickjs/history.c
index a02c453b..945492f7 100644
--- a/src/ecmascript/quickjs/history.c
+++ b/src/ecmascript/quickjs/history.c
@@ -20,6 +20,7 @@
 #include "document/forms.h"
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/history.h"
 #include "ecmascript/quickjs/window.h"
 #include "intl/libintl.h"
@@ -148,7 +149,7 @@ js_history_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
diff --git a/src/ecmascript/quickjs/implementation.c b/src/ecmascript/quickjs/implementation.c
index 89b0758c..abc18ae3 100644
--- a/src/ecmascript/quickjs/implementation.c
+++ b/src/ecmascript/quickjs/implementation.c
@@ -11,6 +11,7 @@
 #include "elinks.h"
 
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/document.h"
 #include "ecmascript/quickjs/implementation.h"
 #include "util/conv.h"
@@ -88,7 +89,7 @@ js_implementation_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValu
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -128,5 +129,5 @@ getImplementation(JSContext *ctx)
 //	JS_SetConstructor(ctx, implementation_class, implementation_obj);
 	JS_SetClassProto(ctx, js_implementation_class_id, implementation_obj);
 
-	return implementation_obj;
+	RETURN_JS(implementation_obj);
 }
diff --git a/src/ecmascript/quickjs/input.c b/src/ecmascript/quickjs/input.c
index fbf0c527..6212d632 100644
--- a/src/ecmascript/quickjs/input.c
+++ b/src/ecmascript/quickjs/input.c
@@ -109,11 +109,13 @@ js_input_get_property_accessKey(JSContext *ctx, JSValueConst this_val)
 	}
 
 	if (!link->accesskey) {
-		return JS_NewStringLen(ctx, "", 0);
+		JSValue r = JS_NewStringLen(ctx, "", 0);
+		RETURN_JS(r);
 	} else {
 		const char *keystr = encode_utf8(link->accesskey);
 		if (keystr) {
-			return JS_NewString(ctx, keystr);
+			JSValue r = JS_NewString(ctx, keystr);
+			RETURN_JS(r);
 		} else {
 #ifdef ECMASCRIPT_DEBUG
 	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
@@ -226,7 +228,8 @@ js_input_get_property_alt(JSContext *ctx, JSValueConst this_val)
 	assert(fc);
 	assert(fc->form && fs);
 
-	return JS_NewString(ctx, fc->alt);
+	JSValue r = JS_NewString(ctx, fc->alt);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -408,7 +411,8 @@ js_input_get_property_defaultValue(JSContext *ctx, JSValueConst this_val)
 	assert(fc->form && fs);
 
 	/* FIXME (bug 805): convert from the charset of the document */
-	return JS_NewString(ctx, fc->default_value);
+	JSValue r = JS_NewString(ctx, fc->default_value);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -631,7 +635,8 @@ js_input_get_property_name(JSContext *ctx, JSValueConst this_val)
 	assert(fc);
 	assert(fc->form && fs);
 
-	return JS_NewString(ctx, fc->name);
+	JSValue r = JS_NewString(ctx, fc->name);
+	RETURN_JS(r);
 }
 
 /* @input_class.setProperty */
@@ -937,7 +942,8 @@ js_input_get_property_src(JSContext *ctx, JSValueConst this_val)
 	if (linknum >= 0) link = &document->links[linknum];
 
 	if (link && link->where_img) {
-		return JS_NewString(ctx, link->where_img);
+		JSValue r = JS_NewString(ctx, link->where_img);
+		RETURN_JS(r);
 	} else {
 		return JS_UNDEFINED;
 	}
@@ -1100,7 +1106,8 @@ js_input_get_property_type(JSContext *ctx, JSValueConst this_val)
 	default: INTERNAL("input_get_property() upon a non-input item."); break;
 	}
 
-	return JS_NewString(ctx, s);
+	JSValue r = JS_NewString(ctx, s);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -1119,7 +1126,8 @@ js_input_get_property_value(JSContext *ctx, JSValueConst this_val)
 		return JS_NULL; /* detached */
 	}
 
-	return JS_NewString(ctx, fs->value);
+	JSValue r = JS_NewString(ctx, fs->value);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -1403,7 +1411,7 @@ js_input_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst *a
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -1447,7 +1455,8 @@ getInput(JSContext *ctx, struct form_state *fs)
 	auto node_find = map_inputs.find(fs);
 
 	if (node_find != map_inputs.end()) {
-		return JS_DupValue(ctx, node_find->second);
+		JSValue r = JS_DupValue(ctx, node_find->second);
+		RETURN_JS(r);
 	}
 	JSValue input_obj = JS_NewObjectClass(ctx, js_input_class_id);
 
@@ -1457,5 +1466,6 @@ getInput(JSContext *ctx, struct form_state *fs)
 	fs->ecmascript_obj = input_obj;
 	map_inputs[fs] = input_obj;
 
-	return JS_DupValue(ctx, input_obj);
+	JSValue rr = JS_DupValue(ctx, input_obj);
+	RETURN_JS(rr);
 }
diff --git a/src/ecmascript/quickjs/localstorage.c b/src/ecmascript/quickjs/localstorage.c
index 843a2f59..4abfbfb4 100644
--- a/src/ecmascript/quickjs/localstorage.c
+++ b/src/ecmascript/quickjs/localstorage.c
@@ -22,6 +22,7 @@
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
 #include "ecmascript/localstorage-db.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/localstorage.h"
 #include "intl/libintl.h"
 #include "main/select.h"
@@ -76,7 +77,6 @@ readFromStorage(const unsigned char *key)
 static void
 saveToStorage(const unsigned char *key, const unsigned char *val)
 {
-
 	if (local_storage_ready==0) {
 		db_prepare_structure(local_storage_filename);
 		local_storage_ready=1;
@@ -100,8 +100,6 @@ js_localstorage_getitem(JSContext *ctx, JSValueConst this_val, int argc, JSValue
 #ifdef ECMASCRIPT_DEBUG
 	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
 #endif
-	struct ecmascript_interpreter *interpreter = (struct ecmascript_interpreter *)JS_GetContextOpaque(ctx);
-
 	if (argc != 1)
 	{
 		return JS_UNDEFINED;
@@ -116,17 +114,16 @@ js_localstorage_getitem(JSContext *ctx, JSValueConst this_val, int argc, JSValue
 		return JS_EXCEPTION;
 	}
 
-	if (key) {
-		unsigned char *val = readFromStorage(key);
+	unsigned char *val = readFromStorage(key);
+	JS_FreeCString(ctx, key);
 
-		JSValue ret = JS_NewString(ctx, val);
-
-		mem_free(val);
-		JS_FreeCString(ctx, key);
-		return ret;
+	if (!val) {
+		return JS_NULL;
 	}
 
-	return JS_UNDEFINED;
+	JSValue ret = JS_NewString(ctx, val);
+	mem_free(val);
+	RETURN_JS(ret);
 }
 
 /* @localstorage_funcs{"setItem"} */
@@ -197,7 +194,7 @@ js_localstorage_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueC
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -207,20 +204,23 @@ fail:
 int
 js_localstorage_init(JSContext *ctx, JSValue global_obj)
 {
-	JSValue localstorage_proto, localstorage_class;
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	static int initialized;
 
-	/* create the localstorage class */
-	JS_NewClassID(&js_localstorage_class_id);
-	JS_NewClass(JS_GetRuntime(ctx), js_localstorage_class_id, &js_localstorage_class);
+	if (!initialized) {
+		/* create the localstorage class */
+		JS_NewClassID(&js_localstorage_class_id);
+		JS_NewClass(JS_GetRuntime(ctx), js_localstorage_class_id, &js_localstorage_class);
+		initialized = 1;
+	}
 
-	localstorage_proto = JS_NewObject(ctx);
-	JS_SetPropertyFunctionList(ctx, localstorage_proto, js_localstorage_proto_funcs, countof(js_localstorage_proto_funcs));
+	JSValue localstorage_obj = JS_NewObjectClass(ctx, js_localstorage_class_id);
+	JS_SetPropertyFunctionList(ctx, localstorage_obj, js_localstorage_proto_funcs, countof(js_localstorage_proto_funcs));
+	JS_SetClassProto(ctx, js_localstorage_class_id, localstorage_obj);
 
-	localstorage_class = JS_NewCFunction2(ctx, js_localstorage_ctor, "localStorage", 0, JS_CFUNC_constructor, 0);
-	/* set proto.constructor and ctor.prototype */
-	JS_SetConstructor(ctx, localstorage_class, localstorage_proto);
-	JS_SetClassProto(ctx, js_localstorage_class_id, localstorage_proto);
+	JS_SetPropertyStr(ctx, global_obj, "localStorage", localstorage_obj);
 
-	JS_SetPropertyStr(ctx, global_obj, "localStorage", localstorage_proto);
 	return 0;
 }
diff --git a/src/ecmascript/quickjs/location.c b/src/ecmascript/quickjs/location.c
index d67b8ce1..ccf829a2 100644
--- a/src/ecmascript/quickjs/location.c
+++ b/src/ecmascript/quickjs/location.c
@@ -20,6 +20,7 @@
 #include "document/forms.h"
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/location.h"
 #include "ecmascript/quickjs/window.h"
 #include "intl/libintl.h"
@@ -72,7 +73,7 @@ js_location_get_property_hash(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewStringLen(ctx, fragment.source, fragment.length);
 	done_string(&fragment);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -103,7 +104,7 @@ js_location_get_property_host(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewString(ctx, str);
 	mem_free(str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -134,7 +135,7 @@ js_location_get_property_hostname(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewString(ctx, str);
 	mem_free(str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -165,7 +166,7 @@ js_location_get_property_href(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewString(ctx, str);
 	mem_free(str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -196,7 +197,7 @@ js_location_get_property_origin(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewString(ctx, str);
 	mem_free(str);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -226,7 +227,7 @@ js_location_get_property_pathname(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewStringLen(ctx, pathname.source, pathname.length);
 	done_string(&pathname);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -254,7 +255,7 @@ js_location_get_property_port(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewStringLen(ctx, port.source, port.length);
 	done_string(&port);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -287,7 +288,7 @@ js_location_get_property_protocol(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewStringLen(ctx, proto.source, proto.length);
 	done_string(&proto);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -318,7 +319,7 @@ js_location_get_property_search(JSContext *ctx, JSValueConst this_val)
 	JSValue ret = JS_NewStringLen(ctx, search.source, search.length);
 	done_string(&search);
 
-	return ret;
+	RETURN_JS(ret);
 }
 
 static JSValue
@@ -613,7 +614,7 @@ js_location_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -638,5 +639,5 @@ js_location_init(JSContext *ctx, JSValue global_obj)
 	JS_SetClassProto(ctx, js_location_class_id, location_proto);
 
 	JS_SetPropertyStr(ctx, global_obj, "location", location_proto);
-	return location_proto;
+	RETURN_JS(location_proto);
 }
diff --git a/src/ecmascript/quickjs/navigator.c b/src/ecmascript/quickjs/navigator.c
index 74d73348..41fe94c2 100644
--- a/src/ecmascript/quickjs/navigator.c
+++ b/src/ecmascript/quickjs/navigator.c
@@ -20,6 +20,7 @@
 #include "document/forms.h"
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/navigator.h"
 #include "intl/libintl.h"
 #include "main/select.h"
@@ -53,7 +54,8 @@ js_navigator_get_property_appCodeName(JSContext *ctx, JSValueConst this_val)
 #ifdef ECMASCRIPT_DEBUG
 	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
 #endif
-	return JS_NewString(ctx, "Mozilla"); /* More like a constant nowadays. */
+	JSValue r = JS_NewString(ctx, "Mozilla"); /* More like a constant nowadays. */
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -62,7 +64,8 @@ js_navigator_get_property_appName(JSContext *ctx, JSValueConst this_val)
 #ifdef ECMASCRIPT_DEBUG
 	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
 #endif
-	return JS_NewString(ctx, "ELinks (roughly compatible with Netscape Navigator, Mozilla and Microsoft Internet Explorer)");
+	JSValue r = JS_NewString(ctx, "ELinks (roughly compatible with Netscape Navigator, Mozilla and Microsoft Internet Explorer)");
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -71,7 +74,8 @@ js_navigator_get_property_appVersion(JSContext *ctx, JSValueConst this_val)
 #ifdef ECMASCRIPT_DEBUG
 	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
 #endif
-	return JS_NewString(ctx, VERSION);
+	JSValue r = JS_NewString(ctx, VERSION);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -82,7 +86,8 @@ js_navigator_get_property_language(JSContext *ctx, JSValueConst this_val)
 #endif
 #ifdef CONFIG_NLS
 	if (get_opt_bool("protocol.http.accept_ui_language", NULL)) {
-		return JS_NewString(ctx, language_to_iso639(current_language));
+		JSValue r = JS_NewString(ctx, language_to_iso639(current_language));
+		RETURN_JS(r);
 	}
 #endif
 	return JS_UNDEFINED;
@@ -94,7 +99,8 @@ js_navigator_get_property_platform(JSContext *ctx, JSValueConst this_val)
 #ifdef ECMASCRIPT_DEBUG
 	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
 #endif
-	return JS_NewString(ctx, system_name);
+	JSValue r = JS_NewString(ctx, system_name);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -127,10 +133,12 @@ js_navigator_get_property_userAgent(JSContext *ctx, JSValueConst this_val)
 			safe_strncpy(custr, ustr, 256);
 			mem_free(ustr);
 
-			return JS_NewString(ctx, custr);
+			JSValue r = JS_NewString(ctx, custr);
+			RETURN_JS(r);
 		}
 	}
-	return JS_NewString(ctx, system_name);
+	JSValue rr = JS_NewString(ctx, system_name);
+	RETURN_JS(rr);
 }
 
 static const JSCFunctionListEntry js_navigator_proto_funcs[] = {
@@ -164,7 +172,7 @@ js_navigator_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueCons
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
diff --git a/src/ecmascript/quickjs/nodelist.c b/src/ecmascript/quickjs/nodelist.c
index 1f34cf97..22a865c5 100644
--- a/src/ecmascript/quickjs/nodelist.c
+++ b/src/ecmascript/quickjs/nodelist.c
@@ -20,6 +20,7 @@
 #include "document/forms.h"
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/element.h"
 #include "ecmascript/quickjs/nodelist.h"
 #include "ecmascript/quickjs/window.h"
@@ -171,7 +172,7 @@ js_nodeList_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -214,6 +215,5 @@ getNodeList(JSContext *ctx, void *node)
 	JS_SetOpaque(nodeList_obj, node);
 	js_nodeList_set_items(ctx, nodeList_obj, node);
 
-	return nodeList_obj;
+	RETURN_JS(nodeList_obj);
 }
-
diff --git a/src/ecmascript/quickjs/screen.c b/src/ecmascript/quickjs/screen.c
index c38c2fe3..0268ea0e 100644
--- a/src/ecmascript/quickjs/screen.c
+++ b/src/ecmascript/quickjs/screen.c
@@ -20,6 +20,7 @@
 #include "document/forms.h"
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/screen.h"
 #include "ecmascript/quickjs/window.h"
 #include "intl/libintl.h"
@@ -161,7 +162,8 @@ js_screen_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst *
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
diff --git a/src/ecmascript/quickjs/unibar.c b/src/ecmascript/quickjs/unibar.c
index 56cf09c4..3d321a34 100644
--- a/src/ecmascript/quickjs/unibar.c
+++ b/src/ecmascript/quickjs/unibar.c
@@ -20,6 +20,7 @@
 #include "document/forms.h"
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/unibar.h"
 #include "ecmascript/quickjs/window.h"
 #include "intl/libintl.h"
@@ -143,7 +144,7 @@ js_menubar_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
@@ -168,7 +169,7 @@ js_statusbar_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueCons
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);
diff --git a/src/ecmascript/quickjs/window.c b/src/ecmascript/quickjs/window.c
index 5949adc2..f1156bda 100644
--- a/src/ecmascript/quickjs/window.c
+++ b/src/ecmascript/quickjs/window.c
@@ -20,6 +20,7 @@
 #include "document/forms.h"
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/quickjs.h"
 #include "ecmascript/quickjs/window.h"
 #include "intl/libintl.h"
 #include "main/select.h"
@@ -254,7 +255,8 @@ js_window_get_property_self(JSContext *ctx, JSValueConst this_val)
 #ifdef ECMASCRIPT_DEBUG
 	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
 #endif
-	return JS_DupValue(ctx, this_val);
+	JSValue r = JS_DupValue(ctx, this_val);
+	RETURN_JS(r);
 }
 
 static JSValue
@@ -405,7 +407,7 @@ js_window_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst *
 	if (JS_IsException(obj)) {
 		goto fail;
 	}
-	return obj;
+	RETURN_JS(obj);
 
 fail:
 	JS_FreeValue(ctx, obj);