When your Emojis are not displayed as desired, it's usually not caused by COYO.
COYO doesn't deliver any emojis by itself, such as Facebook or Whatsapp, but loads them from your operating system in order to not strain the software performance.

You have the possibility to display emojis locally. Chrome, for example, provides the "Chromoji" Add-on. With this add-on emojis are represented quiet accurate. 
Similar add-ons exist for Firefox as well. 

We can't take on any warranty for these, because browser add-ons and their functionality and compatibility are beyond our influence.