use strict;
use warnings;
use WWW::Mechanize::Firefox;
use Data::Dumper;
use DateTime; 
## you can set the date to nearly anything with this module, refer to its documentation

my $mech = WWW::Mechanize::Firefox->new(launch => 
'C:\path\to\your\firefox.exe', 
autoclose => 1, autodie => 1 );

my $jar = $mech->cookies();

print Dumper($jar); # for debugging, you need to understand the data structure of this cookie to properly use it