When we add a smiley 
on a new post on my own discourse forum : the image is replaced by 
Does I need to add some config to change the “127.0.0.1” to the real host name ?
Hiya. 
Do you mean you type :smiley: in the text and it produces :slight_smile: as the output?
I’m not sure, that would depend on how you set up your site. Do you think that is related to your emoji issue? 