Have you looked at perlre and what it says about newlines?

Personally, I don't hand-parse HTML using regular expressions anymore. I use HTML::TreeBuilder::XPath together with HTML::Selector::XPath. There also is a TreeBuilder plugin, WWW::Mechanize::TreeBuilder. A CSS selector for your example could be

    td.Label + td
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so the code for finding the relevant node(s) would be:

my $query = selector_to_xpath('td.Label + td');

my @nodes = $mech->content->findnodes($query);
for (@nodes) {
    print $_->as_HTML;
};
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