var clear_arrows = function() {
for (var i = 0; i < arrows.length; ++i) {
if (arrows[i].svg) {
- arrows[i].svg.parentElement.removeChild(arrows[i].svg);
+ if (arrows[i].svg.parentElement) {
+ arrows[i].svg.parentElement.removeChild(arrows[i].svg);
+ }
delete arrows[i].svg;
}
}
var position_arrow = function(arrow) {
if (arrow.svg) {
- arrow.svg.parentElement.removeChild(arrow.svg);
+ if (arrow.svg.parentElement) {
+ arrow.svg.parentElement.removeChild(arrow.svg);
+ }
delete arrow.svg;
}
if (current_display_line !== null && !current_display_line_is_history) {