if you want to set the duration you have to use an alert instead of notification:
this.sendNotification(“SHOW_ALERT”, {timer: 10000, title: “Title”, message: “Message”});

ok, that did it. The Alerts are now shown as given in the “timer”-argument.
Nevertheless my usecase would be to have also multiple notifications staying on top like “washing machine ready” and “dryer ready” or something which needs some action done.

So it would be nice to have either notification also displayed “on event” and not globally or to have notifications smoothed out, if the item action is done. As I can see, the alert-module doesn’t allow fading the notifications on a action?

{
  module: 'alert',
  config: {
    display_time: 10000
  }
}

if you want to set the duration you have to use an alert instead of notification:

this.sendNotification("SHOW_ALERT", {timer: 10000, title: "Title", message: "Message"});