diff --git a/editor/editor_data.cpp b/editor/editor_data.cpp
index bd6ce797b5..5942348999 100644
--- a/editor/editor_data.cpp
+++ b/editor/editor_data.cpp
@@ -857,11 +857,16 @@ bool EditorData::script_class_is_parent(const String &p_class, const String &p_i
 	if (!ScriptServer::is_global_class(p_class))
 		return false;
 	String base = script_class_get_base(p_class);
+	Ref<Script> script = ResourceLoader::load(ScriptServer::get_global_class_path(p_class), "Script");
+	Ref<Script> base_script = script->get_base_script();
+
 	while (p_inherits != base) {
 		if (ClassDB::class_exists(base)) {
 			return ClassDB::is_parent_class(base, p_inherits);
 		} else if (ScriptServer::is_global_class(base)) {
 			base = script_class_get_base(base);
+		} else if (base_script.is_valid()) {
+			return ClassDB::is_parent_class(base_script->get_instance_base_type(), p_inherits);
 		} else {
 			return false;
 		}