Show no deleted messages in CHQ

nodeletedmessages.user.js

// ==UserScript==
// @name No Deleted Messages
// @description No deleted messages
// @version 0.0.1
// @match http://chat.stackexchange.com/rooms/11540/charcoal-hq
// @author The-Quill
// @run-at document-end
// ==/UserScript==
function hideMessage(message){
    var messageBlock = message.parentNode.parentNode;
    if (messageBlock.classList.contains('deleted')){
        var parentNode = message.parentNode;
        parentNode.removeChild(message);
        if (parentNode.children.length === 0){
            messageBlock.style.display = "none";
        }
    }
}
function nodeInsertionListener(){
    var messages = document.querySelectorAll(".monologue .message");
    Array.prototype.slice.apply(messages).forEach(hideMessage);
}
window.addEventListener("DOMNodeInserted", nodeInsertionListener);