getUniqueText() process passed string as a regular one, it doesn't handle unicode properly and will remove code points parts when several code points share the same numeric parts.
Ultimately, it will result in wrong code points being pushed to output.
The glyphs count will match, not the codes themselves.
Fix subset of UTF-16 glyphs (and probably others).
Keeping getUniqText() method for backward compatibility / third party packages relying on it.