e/Legacy mode

Information
has gloss	eng: In computing, legacy mode is a state in which a computer system, component, or software application behaves in a way different from its standard operation in order to support older software, data, or expected behavior. It differs from backward compatibility in that an item in this state will often sacrifice newer features or performance, or be unable to access data or run programs it normally could, in order to provide continued access to older data or functionality. Sometimes it can allow newer technologies that replaced the old to emulate them when running older operating systems.
lexicalization	eng: legacy mode
instance of	c/Legacy systems