How to extend FORSSA to generate automatic breadcrumbs

Go in View -> Designer Mode, click on Variables and add a variable named, say, "textBreadcrumbs".

Then copy and insert the following code as variable value

{$if nonblank .author$}{$if blank .extra2$}<a href="{$.linkStartPage$}">{$.textSiteLogoHint$}</a> > {$foreach y in (thisFolder)$}
{$if nonblank y.extra2$}<a href="{$y.link$}">{$y.author$}</a> > {$.author$}{$endif$}{$next$}{$endif$}{$if nonblank .extra2$}
<a href="{$.linkStartPage$}">{$.textSiteLogoHint$}</a> > {$.author$}{$endif$}<br><br>{$endif$}

Close the variable window and click on the Templates button. Open the "forssa" template in HTML view (if it opens in normal view, switch to HTML view, close the template without saving changes and open it again).

Replace the section

<!------ MAIN AREA -->
<td bgcolor="{$.colorMainArea$}" valign="top" align="left">
<div class="mainFont"><strong>{$.headline$}</strong><br><br>{$.body$}</div>
</td>

with

<!------ MAIN AREA -->
<td bgcolor="{$.colorMainArea$}" valign="top" align="left">
<div class="mainFont">{$.textBreadcrumbs$}<strong>{$.headline$}</strong><br><br>{$.body$}</div>
</td>

or to put it differently: put the variable {$.textBreadcrumbs$} between <div class="mainFont"> and <strong>.