Package Private Implicit Syntax Class Is Not In Implicit Scope

[adamgfraser]

Minimized code

In ZRef.scala

package zio

trait ZRef

object ZRef {

  private[zio] implicit class ZRefSyntax(private val self: ZRef) extends AnyVal {
    def unsafeUpdate: Boolean = true
  }
}

In Main.scala:

package zio

object Main extends App {
  val ref = new ZRef {}
  println(ref.unsafeUpdate)
}

Output

[error] -- [E008] Not Found Error: /Users/adamfraser/dotty/src/main/scala/zio/Main.scala:5:14 
[error] 5 |  println(ref.unsafeUpdate)
[error]   |          ^^^^^^^^^^^^^^^^
[error]   |value unsafeUpdate is not a member of zio.ZRef, but could be made available as an extension method.
[error]   |
[error]   |The following import might fix the problem:
[error]   |
[error]   |  import zio.ZRef.ZRefSyntax
[error]   |    

Expectation

I would have expected that the implicit syntax would be available within the package. Note that this works if I remove the private[zio] access modifier on the implicit syntax class and it also works as written on Scala 2.

[adamgfraser]

Thank you! 🙏