Dear list,
in the mwe below, the expected result is ok for most entries but fails when the word contains the letters ó or ô.
We get zoolco instead of zoológico, and termtro instead of termômetro. What am I doing wrong?

mwe:

\def\stripnumber#1%
        {\cldcontext{lpeg.match(lpeg.stripper("[¹²³⁴⁵⁶⁷⁸⁹⁰]"), [==[#1]==])}}

\starttext

\stripnumber{árbitro⁶}
\stripnumber{ébano¹}
\stripnumber{ícone⁸}
\stripnumber{zoológico⁰}
\stripnumber{eletroacústico⁹}
\stripnumber{trânsfuga⁷}
\stripnumber{farmacêutico¹}
\stripnumber{maître²}
\stripnumber{termômetro³}
\stripnumber{noûs⁴}

\stoptext
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