Always cast targetlist to const array value, so the iteration remains untouched

code/script/scriptvm.cpp

@@ -644,6 +644,7 @@ void ScriptVM::execCmdMethodCommon(op_parmNum_t param)
             // because if it's a targetlist, the container object can be modified
             // while iterating
 			ScriptVariable array = a;
+			array.CastConstArrayValue();
 
             for (uintptr_t i = arraysize; i > 0; i--) {
                 Listener *const listener = array.listenerAt(i);