I found a bug in the default template file.
When you login using the uni_login plugin your avatar will be set to a remote image. Like this:

http://cdn.akamai.steamstatic.com/steamcommunity/public/images/avatars/3e/3ea7d59c7f3a2ce698fca2174df8c57be1385985_full.jpg

In the layout.tpl file from line 318 it says the following:

<div class="codo_inline_notification_el_img">
    <img src="{{../duri}}assets/img/profiles/icons/{{actor.avatar}}" />
</div>

That means that when you get a notification it will show a broken image because it's trying to create the following link to it:

[YOUR_DOMAIN]/assets/img/profiles/icons/http://cdn.akamai.steamstatic.com/steamcommunity/public/images/avatars/3e/3ea7d59c7f3a2ce698fca2174df8c57be1385985_full.jpg

In other words it's trying to find the remote image in your local files.

I hope this will be resolved soon.Thanks smile