Does anyone have the same issue? Since installing the august update, the system ui disappeared multiple times: The navigation buttons at the bottom of the screen have disappeared, as well as the clock and notification icons at the top. They do still react when I tap where they would have been, but they are just invisible.
The only way to (temporarily) fix this I’ve found so far is to reboot the device.
just to report:
no issue on my device
up to date software version
Happens from time to time.
workaround on my side: lock with side button, unlock with code and not with fingerprint, enter the code on a mixed screen where I see the digits but on the background and then retrieve the normal UI.