The encoding layer is already handling that, so forget about the utf8::decode($_); line and it all just works:

$ cat uct.pl 
#!/usr/bin/perl5.16.3                                                                                            

use strict;
use HTML::Entities;

binmode STDIN, ':encoding(UTF-8)';
binmode STDOUT, ':encoding(UTF-8)';

while(<>) {
    chomp;

    $_ = decode_entities($_);
    $_ = lc($_);

    print $_, "\n";
}
$ echo -e "Édition limitée.\n&Eacute;dition limitée." | perl uct.pl 
édition limitée.
édition limitée.

Update: forgot to mention: this is on perl 5.20.3 regardless of your #! line.

In reply to Re^3: Unexpected interaction between decode_entities() and lc() by hippo
in thread Unexpected interaction between decode_entities() and lc() by kurisuto

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