This article reminds me of the Unicode Japanese "Ghost" characters: https://www.dampfkraft.com/ghost-characters.html
Long story short:
Someone entered some characters erroneously in the Unicode spec and now those characters are there FOREVER.
Long story short:
Someone entered some characters erroneously in the Unicode spec and now those characters are there FOREVER.
The fact that no-one necessarily knows how to read them aloud (some of them you can guess, some of them are very unclear) can be a fun wrinkle.