Hello everyone,
I had the same problem with my s10. Today my phone suddenly refused to output anything on the screen, pitch black. No response, nothing. But the phone was still perfectly fine. When I plugged it in it vibrated per usual indicating it taking a charge and when I shut it off forcibly using the volume down + power button combination it also vibrated indicating a restart. I was stuck on this for 4 hours trying to figure out what hapepned, contacted samsung support to no avail, but eventually I fixed it.
First I unlocked my phone (which removes all forms of passwords to unlock your phone) via the find my phone site from samsung. Then I installed the Dex app on my PC and connected my phone to it after installation. I pressed vaguely in the right-bottom corner which is where the notification of "Do you want to start Dex on this pc" pops up, and the Dex app on my pc flickered for a second and shut itself off. After that my phone screen miraculously turned back on and started working again. I have no idea what caused the problem in the first place but it worked for me and I hope it does for you.
