I think it’s still not supported. But that’s a poor feature. Even in full as3, I would use my own rendering system that would create textefields and Bitmap for each parts, I can share my as3 code if you really need a quick way to add img tags.
It will be cool if you can share your code . I tried to add emoji in textfield ( for chat ) , but using utf codes ( at example ) is not consistent ( i.e wrong space between characters and emoji and overlapping)