This is a workaround for bug #121920 (see https://rt.cpan.org/Public/Bug/Display.html?id=121920)
and effectively reverts changes made in HTML-TableExtract-2.14.

--- HTML-TableExtract-2.15/lib/HTML/TableExtract.pm.orig
+++ HTML-TableExtract-2.15/lib/HTML/TableExtract.pm
@@ -438,7 +438,6 @@
   $self->{_counts}        = [];
   $self->{_in_a_table}    = 0;
   $self->{_parsing}       = 0;
-  $self->tree->delete_content() if TREE();
 }
 
 sub _emsg {