Hello LeonidS 

I have tried all installed templates (Protean Dark and Light Mix, Decorus, Lucid and Ocean) and it is the same with all templates.
I will try with Chrome Developer tools but I am not very confident with it...., that is why I was hoping to get info here if someone else got same trouble with this chat.
It is just as "lets test it" approach to see how it works.....; It integrates with UNA credential just fine so it has some possibility. The problem is also that it is expensive ( see: https://html5-chat.com/purchase ) if one would like to have more then just a free version which is very limited.....