There's one issue with text, it defaults to ASCII:

> For example, for any MIME type whose main type is text, you can add the optional charset parameter to specify the character set used for the characters in the data. If no charset is specified, the default is ASCII (US-ASCII) unless overridden by the user agent's settings. To specify a UTF-8 text file, the MIME type text/plain;charset=UTF-8 is used.

See: https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_...