Robin block

setInterval(function(){
    var blockedUsers = ["cave123", "randomuser123"];
    var deletedMessage = "<Message deleted>";
    var message = document.getElementById("robinChatMessageList").lastElementChild;
    if (message != null && typeof message !== "undefined" && typeof message.getElementsByClassName("robin-message--from") !== "undefined" && typeof message.getElementsByClassName("robin-message--from")[0] !== "undefined" && $.inArray(message.getElementsByClassName("robin-message--from")[0].innerHTML, blockedUsers))
        message.getElementsByClassName("robin-message--message")[0].innerHTML = deletedMessage;
}, 100);