Custom ID field - allow prefix to also contain numbers as well as letters

The recently launched custom ID field is great, but having tried it out, it appears it is currently not possible to use a number within the Prefix of an ID field. :confused:

Hoping we can soon also add numbers along with letters as a prefix, soon! :pray:

:heavy_plus_sign: Bonus points to Asana if we can also include emojis as characters :heart: