My customizations for Slack in Fluid.app

userscript.css

.bot_message {
  	background: #F2F2F2 !important;
  	border-top: 8px solid #F2F2F2;
  	color: #666;
  	margin: 0 !important;
}

.message {
    margin: 4px 0;
}

.message_content {
    margin-left: 200px !important;
}

.message_content > .message_sender {
    position: absolute !important;
    width: 130px !important;
    left: 80px !important;
    text-align: right !important;
    white-space: nowrap;
    text-transform: capitalize;
    overflow: hidden;
    text-overflow: ellipsis;
}

.bot_label {
    display: none !important;
}

#channel_creator_name {
    display: none !important;
}

.inline_attachment[data-real-src*=".giphy.com"] {
    display: none;
}

userscript.js

var clickOverrides = function(){
  // Automatically mark ALL as read and scroll to it
  // when clicking on a channel (stared or normal)
  $('#channel-list, #starred-list').on('click',function(){
    TS.ui.forceMarkAllRead();
    TS.ui.scrollMsgsSoFirstUnreadMsgIsInView();
  });

};

var onMessageClick = function(){
  TS.ui.forceMarkAllRead();
  TS.ui.scrollMsgsSoFirstUnreadMsgIsInView();
};

// Setup and use notification center! Yay.
function wkNotify(title,content,clickCallBack) {
  if (!window.Notification) {
    console.log('not supported');
    return;
  }

  if (Notification.permission === 'denied') {
    console.log("Can't show notification here");

  } else if (Notification.permission === 'default') {
    // Get permission
    Notification.requestPermission(function() {
        notify();
    });

  } else if (Notification.permission === 'granted') {
    var wkNotification = window.webkitNotifications.createNotification(null, title, content);
    if(typeof clickCallBack === "function"){
      wkNotification.onclick = clickCallBack;
    }

    // Show that thing!
    try {wkNotification.show();}
      catch (e) {alert('error: '+e);}
    }
}


// override the growl and use notification center
// wait 10 seconds for everything to load, then do this
setTimeout(function(){
  clickOverrides();
  wkNotify("Loaded custom scripts","");
  TS.ui.growls.show = function(title, text, a,b,c){
    wkNotify(title,text,onMessageClick);
  };
},10000);