Since Tilki he didn't mind, care sharing the template edits you made?
Gladly:
In ACP / Home / Options / [tLk] UsergroupLegend set Auto Template Edit? = Disable
----- Template = sidebar_online_users -----
In template "sidebar_online_users" search for:
PHP:
<div class="footnote">
{xen:phrase online_now_x_members_y_guests_z, 'total={xen:number $onlineUsers.total}', 'members={xen:number $onlineUsers.members}', 'guests={xen:number $onlineUsers.guests}'}
</div>
and after it add this:
PHP:
<xen:include template="tlk_usergroup_legend" />
----- Template = tlk_usergroup_legend -----
Delete the complete content of the template "tlk_usergroup_legend" and use this:
PHP:
<xen:if is="{$TilkiBey_UsergroupLegend}">
<xen:if hascontent="true">
<div class="sectionMain">
<!-- <b>{xen:phrase tlk_usergrouplegend_title}:</b> -->
<xen:contentcheck>
<xen:foreach loop="$TilkiBey_UsergroupLegend" value="$TilkiBey_UsergroupLegend">
~ <span style="{$TilkiBey_UsergroupLegend.usergroup.username_css}" title="{$TilkiBey_UsergroupLegend.usergroup.title}"><b>{$TilkiBey_UsergroupLegend.usergroup.title}</b></span>
</xen:foreach>
</xen:contentcheck>
</div>
</xen:if>
</xen:if>
That's how we use it at Default Style.
If you want a title at the beginning activate the line with the phrase.
In other styles i've changed the sectionMain to an own class with settings in the template "EXTRA.css".