What authority assigns the "short" names of the Emoji?

[elijah (Eli the Bearded)]

UTR#51 deals with emoji, but they don’t seem to deal with assigning short codes. It is merely vaguely touched on in the section on Input:

6 Input - UTS #51: Unicode Emoji

In some input systems, a word or phrase bracketed by colons is used to explicitly pick emoji characters. Thus typing in “I saw an #x3a;ambulance:” is converted to “I saw an ”. For completeness, such systems might support all of the full Unicode names, such as :first quarter moon with face: for . Spaces within the phrase may be represented by _, as in the following:

“my didn’t work”

→

“my didn’t work”.

However, in general the full Unicode names are not especially suitable for that sort of use; they were designed to be unique identifiers, and tend to be overly long or confusing.

However while works here: other names like do not.