You can also use HTML::TreeBuilder to parse the HTML and use HTML::Element's dumping methods for pretty-printing:

my $tree = HTML::TreeBuilder->new; # empty tree
$tree->parse( $res->content );
$tree->eof;   # tells it to parse the whole thing
# Straight content dump
$tree->dump;
# HTML-formatted
print $tree->as_HTML;
# Just the text
print $tree->as_trimmed_text;
# Cleanup the tree
$tree->delete;
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