texmath-0.13.1.2: test/roundtrip/msup-08.native

[ ESuper (ENumber "2") (ESuper (ENumber "3") (ENumber "4"))
, ESymbol Rel "="
, ESuper
    (ENumber "2")
    (ESuper
       (ENumber "3") (EOver False (ENumber "4") (EPhantom (ENumber "5"))))
]