When renaming any item in a anvil to Unicode characters, the game will replace the Unicode characters with (, *, and ?. (possibly replacement characters?). Renaming a item in a anvil that already has been renamed with Unicode characters will not work. The anvil shouldn't allow items to be renamed to Unicode characters, (at least in survival).

Picture 1: Bugged renamed chest.
Picture 2: Attempting to rename chest (character translation before and after)