I mentioned it in the other topic, but probably better to have this in its own thread. The root cause may well be the same.
If I put a unicode emoji in a post, it doesn’t get normalised in the preview pane. When it’s cooked server-side, the normalisation happens properly. For example:
Je transfère cela à Contribute > UX et j’ajoute un pr-welcome. C’est si subtil, mais je pense que je soutiens la modification pour que cela se normalise.