Exactly the same issue on my S10!
I woke up, grabbed my phone from the wireless charger and had a difficulty turning it on. The white bar is covering about 1/5th of the bottom screen. No crack in the screen whatsoever. Everything covered by the white bar still works fine (fingerprint scanner, typing, etc.), but impossible to get rid of it even in safe mode.
A quick search shows this is happening to a lot of people, and most have said they had to replace the screen on their own dime. This is already my second S10, the first one died after the battery simply stopped charging. Gonna be so angry if it's not covered under warranty, I never even dropped it once since I bought this 4 months ago.
