In trying to fix #47404, we noticed that it's really hard to read UTF16 data from files. Long ago there used to be utf16() and utf32() functions to do the conversion, but they were deprecated and removed.

The prevailing narrative is "UTF8 everywhere," and I agree wholeheartedly. But, reading UTF16 and UTF32 data, especially from a file, and converting to UTF8 ought to be easier.