Function content 

pub fn content(bytes: Vec<u8>) -> String

The content of a file of bytes, as a workspace holds it: a file holds text, so the text they spell where they are UTF-8 throughout, and otherwise — a binary STL, a STEP file with a Latin-1 name in it — a data: URL of them in base64. A front end reading a file a user chose holds it the same way, so files travel as text everywhere and only what reads bytes (bytes) or text (text) decodes them.