Emacs: Update Unicode Data
Unicode has a new version every year. Emacs's unicode info used by describe-char may not be up-to-date. (it doesn't know the new characters).
You can make emacs use the latest unicode data.
Download the latest UnicodeData.txt at https://www.unicode.org/Public/UCD/latest/ucd/UnicodeData.txt
Put that file in your emacs init dir.
put this in your Emacs Init File:
(when (file-exists-p "~/.emacs.d/UnicodeData.txt") (setq describe-char-unicodedata-file "~/.emacs.d/UnicodeData.txt"))