Why not use the open pragma  use open qw(:std :utf8); ORbinmode like so: binmode FILEHANDLE, LAYER. i.e 

open DEBUGFILE, '>', "debug.txt" or die $!;
binmode DEBUGFILE, ":encoding(UTF-8)";

[download]

Using your OP, I don't have Win32::IE::Mechanize, installed so I used WWW::Mechanize, like so:
use WWW::Mechanize;
...
# get the DOM document
#my $doc = $mech->{agent}->Document; # comment out

# get the webpage title
my $title = $mech->title;     # used instead
...
# create a utf-8 text file
open DEBUGFILE, '>', "debug.txt" or die $!;
binmode DEBUGFILE,":encoding(UTF-8)";
...

[download]
OUTPUT:
Title:야후! 코리아
Title Length:7
Title Hex Byte String:c74c120245ca44
Hope this helps

If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me

In reply to Re: How to handle UTF-8 content with Win32::IE::Mechanize by 2teez
in thread How to handle UTF-8 content with Win32::IE::Mechanize by Anonymous Monk

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