Hi,
author plugin is the same from version 1.x

Why happen?
Joomla add author meta tag in HTML HEAD in the article page like this:

<meta name="author" content="AUTHOR NAME" />

"Easy Profile - Author" plugin convert author name into link to profile page.
Normally Joomla articles trigger content plugins (like our plugin) and specify the purpose (for example if it is article page or category page).
In category page for example there is not author meta tag because in the category you can have many articles from many authors.
Our plugin check the purpose, so if the purpose is "article page" set meta tag author without add a link. But your page not come from Joomla Article, this is article from "com_tz_portfolio". The bug is into "com_tz_portfolio", it not specify the correct purpose when it trigger content plugins.

I hope you can understand my explanation.

You will never find this code, this is generated by Joomla with function JDocument->setMetaData('author',$var)

Hi,
sorry we can't help you to find where com_tz_portfolio component load meta tag, you need to contact the developer.

Anyway, keep in mind that JDocument->setMetaData is only an example, JDocument can be a variable, so you will never find this string.

We explain you why this happen to point you on right way, but we not have experience with this component.

Hi,
we can't fix problems of other extensions, but you can try this workaround, in file /plugins/content/jsn_author/jsn_author.php at line 17 add this code:

if( JFactory::getApplication()->input->get( 'option' , '' ) != 'com_content' ) return;

with this author plugin will work only on Joomla Article pages