Hi pavit and thank you very much for your help.
Ok, typography plugin updated to latest 1.0.4 and message on backend dissapeared. Now I have the message on frontpage in every article: Warning: count(): Parameter must be an array or an object that implements Countable in /usr/home/simfoniametallica.com/web/templates/gkrockwall/html/comcontent/article/default.php on line 13
I guess it's from the template? Sorry about all my questions, I'm not an expert, just a user of joomla.