WDE Emojis appear as questionmarks

As stated in the title, in Workspace Desktop Edition, when I choose one or more emoticons from the panel a problem in its display comes up. Especially, although inside the blank editable text space the emoticons (emojis) are rendered (or whatever the correct word for that is...) fine, as expected, when I actually send the message, in the chat trascript just above this does not happen. Each of them is displayed as a questionmark both in the WDE and the Web Portal side.
If you copy the emoticon in the Web Portal and then press Send from the customer side then it shows correctly! Please see the next image:



Any advice would be helpful.
Thanks,
Andreas