@janne The problem here might be that you are specifically using iOS emojis. There are several issues in the web using iOS emojis with Roboto.
I think (!) Roboto does not include the unicode conversion for every emoji.
As you can see above, Android worked at least for the more common ones. iOS might be a problem.
Maybe this emoji font family on github can help but I’m not sure how it could be implemented on a mirror.
A New Chapter for MagicMirror: The Community Takes the Lead
Read the statement by Michael Teeuw here.
Read the statement by Michael Teeuw here.