I’ve tried the example from here: Mailboxes • Akka Documentation with…
ActorSystem.create(Behaviors.setup(ctx -> someBehavior(ctx)), "system", ConfigFactory.load("application.conf"), MailboxSelector.fromConfig("my-app.my-special-mailbox")); …with the configuration copied from the link above, just an own mailbox class (with the appropriate constructor).
But it didn’t work at all. No errors or similar, but the guardian actor’s mailbox was simply not changed from the default.
When I tried to set the mailbox of a child actor, it worked totally fine as expected.
Is this a known limitation? Or a bug? Same behavior seems to happen with scaladsl, see here: scala - Akka: Priority Mailbox not working with Akka Typed - Stack Overflow