Since that module uses HTML::TokeParser for parsing the html, you should sheck the HTML::TokeParser documentation, which says:

Note that the parsing result will likely not be valid if raw undecoded UTF-8 is used as a source. When parsing UTF-8 encoded files turn on UTF-8 decoding:

   open(my $fh, "<:utf8", "index.html") || die "Can't open 'index.html
+': $!";
   my $p = HTML::TokeParser->new( $fh );
   # ...
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If a $filename is passed to the constructor the file will be opened in raw mode and the parsing result will only be valid if its content is Latin-1 or pure ASCII.

If parsing from an UTF-8 encoded string buffer decode it first:

   utf8::decode($document);
   my $p = HTML::TokeParser->new( \$document );
   # ...
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