It's nearly impossible to know or to implement all utf-8/16 as beside of UTF support you need also to provide fonts for each. Thousands of scalable fonts - takes a lot of memory. That's why using such characters is risky as somewhere on the path such font will be displayed aa trash. (logs to email to presentation to word to excel to csv to database for example)

For years Ł support on Python on windows for example broke sometimes when imported from poor quality Excel files haha