It can be done. It's a bit long winded but can be done. Here goes
Open whatsapp
Go into settings
Go into notifications
Toggle on use high priority notifications. Do this for both messages and groups
Choose a contact or group you want to have pop up notifications from
Click 3 dots top right, Click on view contact
Click on custom notifications and ensure use custom notifications are ticked.
Do this for each contact and groups you want.
Then in your phones settings goto notifications
Goto advanced settings
Goto conversations
You will see a list of all the contacts you just assigned.
Click on each one and ensure show as pop up is toggled on.
Hopefully you should now get popups!
