Graham Mwebvendor Just wrap the actual <img> tag in the 'if' statement not the whole <a> tag ie

<a href="{{ comment.author_profile.link }}">{% if ctx.data.device != 'mobile' %}<img src="{{ comment.author_profile.avatars[16] }}" style="display:inline" />{% endif %}{{ comment.author_profile.name }}</a>

Note that I used ctx.data.device not just data.device in this instance because it is within the comment macro function

As for the other issue I will try to test it myself and get back to you on that