After a recent update (Android 9.0), I have noticed that Whatsapp Messenger notifications come up similar to how Facebook Messenger notifications are delivered - with a chat head. This is a circle with the messenger's profile picture showing, and clicking on it opens a small window with the message shown.
I preferred when this chat head was never there, and I got to see a preview of the message for a few seconds just below the top of the screen when a message arrives. Is it possible to turn this feature off? I have tried turning off pop-up notifications, but this seems to be something different entirely, as the chat heads continue to come up.