Non-ASCII text seems to be garbled.
Creating template Rust project and modifying string literal in the first `text` call to contain non-ASCII UTF-8 bytes makes the game output garbled text, as if it were interpreting the bytes it as CP1252 instead of UTF-8.

This contradicts with the name of function `textUtf8`.

Inspecting the cartridge with `wasm2wat` shows that the string inside is indeed UTF-8.