[Lynne]

You mean what is the variable in the template? Here is the relevant code from the template activitystream_forum_thread

	<vb:if condition="$userinfo['showavatar']">
		<div class="avatar">
			<img src="{vb:raw userinfo.avatarurl}" alt="{vb:rawphrase xs_avatar, {vb:raw userinfo.username}}" />
		</div>
	</vb:if>