Yes, the screen saver, if you prefer.
During the manual update, there are many packages being downloaded and installed. My phone locked the screen a few times, but I was able to unlock it by entering the security code. On the last lock, there was no unlock screen anymore. After a while, the screen came back with the error “RPM failed” (see screenshot) and a retry started automatically. I then keep touching the screen to prevent to lock and the update process finished successfully.