So my question : who has corrupted Clémence ?
As far as I can tell, XML::Twig::print did. It seems to me (from your post) the problem goes away with keep_encoding => 1? 
sub print {
    ...
    if($perl_version > 5.006 && ! $t->{twig_keep_encoding}) 
      { if( grep /useperlio=define/, `$^X -V`)
          { binmode( $fh || \*STDOUT, ":utf8" ); }
      }
    ...

[download]
Since you didn't use utf8; in your code, Clémence is not utf-8 (for Perl's purposes). Printing it to utf-8 filehandle will wreck Clémence.

Also I don't understand what utf-8 has to do with Perl 5.018 in particular

In reply to Re: Lost in encoding in Twig by Anonymous Monk
in thread Lost in encoding in Twig by pcouderc

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