texmath-0.12.5: test/roundtrip/msubsup-11.native

[ ESubsup (EIdentifier "T") (EIdentifier "m") (EIdentifier "n")
, ESymbol Rel "="
, EOver
    False
    (ESubsup (EIdentifier "T") (EIdentifier "m") (EIdentifier "n"))
    (EPhantom (EText TextNormal "x"))
]