sub to_json_hash {
my $pos = shift;
- my $json = { %$pos, board => undef, fen => $pos->fen() };
+ my $json = { %$pos, board => undef, prettyprint_cache => undef, fen => $pos->fen() };
if ($json->{'player_w'} =~ /^base64:(.*)$/) {
$json->{'player_w'} = MIME::Base64::decode_base64($1);
}