codepoint exceeded 0x10000. So Unicode has solve it by creating Surrogate code points. Surrogate code points are code points that are not assigned by all Unicode encoding form. UTF-16 use this Surrogate zone to express code points that are exceeded 0x10000 by combine two code point.
as javascript. So any(.) match 1 code point but not 1 character, if string contains surrogate pair. So how do we treat surrogate pair with RegExp easily?