Unprocessable Entity (422) when uploading file with non-English name

With the following code:

import cats.effect._
import org.http4s._
import org.http4s.dsl.io._
import org.http4s.multipart._

object TestService {
  val service = HttpService[IO] {
    case req @ POST -> Root / "test" =>
      req.decode[Multipart[IO]](_ => Ok("Done"))
  }
}

I tried Thai, Japanese and Chinese file names. The server always return HTTP 422. English names work fine though. Example names that fail: ทดสอบ, テスト and 实验.

[jmcardon]

I think utf8 as a default is ok. Seems like everyone else is ignoring that part of the rfc…

[tenniscp25]

Thanks!