https://www.cnet.com/news/samsung-may-add-in-screen-camera-and-fingerprint-sensor-to-future-phones/

It's not clear whether these features would show up in the Galaxy S10 or other future phones. If they do, it'll mean the display could fill up the whole phone screen. 

Tipster Samsung Mobile News also tweeted about the rumors, saying: "Samsung is working on a new technology trying to hide the front camera underneath the display. My sources told me that there are just a hand full of prototypes using this technology. I don't think we'll see this feature in retail phones until 2020, but who knows."