Same here on my S8 after update. I will only occasionally get a notification badge, but not like it used to be before the update.
For instance, before the update I used to go to Facebook and read all of my notifications. After an hour or so, I would have a notification badge that showed 10 notifications. Now when I do this, I get none after an hour. But if i go into FB, shows 10-15 unread. I turned ALL notifications for FB on trying to troubleshoot and haven't been able to figure it out...
Then only occasionally I will get a badge....