clone.diff

diff --git a/lib/Mojo/DOM/HTML.pm b/lib/Mojo/DOM/HTML.pm
index 97e1d25..59d5a29 100644
--- a/lib/Mojo/DOM/HTML.pm
+++ b/lib/Mojo/DOM/HTML.pm
@@ -3,6 +3,7 @@ use Mojo::Base -base;
 
 use Mojo::Util qw(html_unescape xml_escape);
 use Scalar::Util 'weaken';
+use Storable 'dclone';
 
 has tree => sub { ['root'] };
 has 'xml';
@@ -101,7 +102,10 @@ my %BLOCK = map { $_ => 1 } (
 );
 
 sub parse {
-  my ($self, $html) = (shift, "$_[0]");
+  my ($self, $html) = @_;
+
+  return $self->tree(dclone $html->tree)->xml($html->xml)
+    if ref $html && $html->isa('Mojo::DOM');
 
   my $xml = $self->xml;
   my $current = my $tree = ['root'];