var start_display_move_num = 0;
if (hash_refutation_lines) {
base_line = current_display_line.pretty_pv.slice(0, current_display_move + 1);
var start_display_move_num = 0;
if (hash_refutation_lines) {
base_line = current_display_line.pretty_pv.slice(0, current_display_move + 1);