Do you mean if you post just emojis, or text and emojis?
@Francesca, if I try to preview text in a comment box which includes emojis from my iPad keyboard I get a message saying I have left the comment box empty, as if there is no text in it. If I remove the iPad emojis and leave the text, I can then preview the comment without problems.
The forum emojis do not cause this issue for me.
I’ve attempted to attach a screen shot of this message along with a non forum bee emoji from my keyboard.
It doesn’t seem to matter which keyboard emoji I choose.