synchronized (newReplies) {
boolean isNew = !knownReplies.contains(replyId) && newReplies.remove(replyId);
knownReplies.add(replyId);
synchronized (newReplies) {
boolean isNew = !knownReplies.contains(replyId) && newReplies.remove(replyId);
knownReplies.add(replyId);