i replied back in pm and this is mostly likely solved.
For anyone else who is looking for this for quark, this code will work.
.thread_view .messageList .messageUserInfo a.avatar img,
.thread_view .quickReply .messageUserInfo a.avatar img,
.conversation_view .messageList .messageUserInfo a.avatar img,
.conversation_view .quickReply .messageUserInfo a.avatar img,
.avatar img, .avatar .img, .avatarCropper
{
max-width: 142px;
height: auto;
}
.messageUserInfo { width: 160px !important; }
.messageUserBlock .arrow { right: -10px !important; }
.messageUserBlock .arrow span { left: -11px !important; }
.messageUserBlock h3.userText { width: 140px !important; }
.messageUserBlock div.uix_avatarHolderInner { max-width: 142px !important; }
#QuickReply { margin-left: 180px !important; }
<xen:if is="@enableResponsive">
@media (max-width:@maxResponsiveNarrowWidth)
{
.thread_view .messageList .messageUserInfo a.avatar img,
.thread_view .quickReply .messageUserInfo a.avatar img,
.conversation_view .messageList .messageUserInfo a.avatar img,
.conversation_view .quickReply .messageUserInfo a.avatar img
{
width: 48px;
height: auto;
}
.avatarHolder .userMood img {
display: none;
}
}
</xen:if>