Javascript is not the problem it is access to the DOM. For simple javascript you can do something like this:

our @URLS;
my $runtime = JavaScript::Runtime->new();;
my $context = $runtime->create_context();
$context->bind_function(
  name => 'open', func => sub {
    push(@URLS, @_);
    return 0;
} );
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Then

$context->eval(q(open("http://bob.com/")))
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will push http://bob.com/ onto @URLS.