Then they are not up-to-date (at least WWW::Mechanize isn't up to date, the version on activestate's repository is ancient).

I'm not sure how to turn on debugging though, I've tried

perldoc LWP::Debug

use LWP::UserAgent;
$ua = LWP::UserAgent->new;
$ua->default_header('Accept-Encoding' => scalar HTTP::Message::decodab
+le());

$ua->add_handler("request_send",  sub { shift->dump; return });
$ua->add_handler("response_done", sub { shift->dump; return });

$ua->get("http://www.example.com");
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