XF 2.1 Subtitle on index page XF2

[dondomainer]

I am trying to add a subtitle on index // like

Mystie - my subtitle.

on the template, page container.

<title><xf:title formatter="%s | %s" fallback="{$xf.options.boardTitle}" page="{$pageNumber}" /></title>

i try with this conditional

<xf:if is="$template == 'page_container'">

     My subtitle

</xf:if>

but it does not work, How can I achieve this?..

Best regards

 

[dondomainer]

Plz, Nobody ?