After upgraded to Oreo beta, I don't see any app icons that shows red dot with numbers on it. Now they replaced red dot with blue dot on app icon which I didn't like. Please bring red dot with number back, I loved it
the red dot with numbers is replaced by colored dot that mean you have a notification in Oreo. If you want to know details of the notification just keep touching a second or 2 on it and you'll see the content of the notification.
Oreo's notification system changed from the roots (Google not Nokia).
Maybe Nova Launcher as custom behavior like you love, but I'm not sure. :-)