UTF-16 surrogate pairs largely unsupported

If you take the character "[ok, so GitHub also does not support this character, but it is the one you can copy/paste from this website: http://www.codetable.net/decimal/119558]" and paste it into an ACE instance, it looks pretty much ok, but it acts as if it were not one, but two characters: you can actually position your cursor halfway through the character, and you are further able to delete either only the first or only the second half. I presume (but might totally be off-base) that this is because this character is too high to be represented as UCS-2 (as in, is a non-BMP character), and thereby uses a UTF-16 surrogate pair; as JavaScript strings are more akin to a C array than a real string, the underlying representation in the string type involves both individual "characters" (really, "UTF-16 code units" in this particular case). Is it possible for characters like this to become better supported?