FYI this update messed up faceid. Had to fiddle with its settings to get it back to work…
Reading apple forums it seems it rarely happens with updates on specific devices with supposedly faulty sensors. Faulty like in not 100%.
My iPhone was repaired with full screen replacement when I bought it refurbished, I guess it’s a warning shot 🙂↕️
"Messed up" : faceid still on but not working at all to unlock device or apps. Even after a reboot. Can't turn it off, can't add alternative face because primary face detection fails.
Here is what worked, as I read in apple forum: go in faceid settings, on the top block click "Learn more..." scroll all the way to the bottom. Turn faceid off for all apps in "use faceid for:" menu, then on. I know this is not a fix, not supposed to do anything useful, but it worked. It's pretty unnerving, hope I won't get that ever again, as I think it may very well be related to sensors failing progressively (again my device was a return for repair refurbished one)
Pseudo scientific source on apple forums https://discussions.apple.com/thread/255768527?sortBy=rank
Edit: typos, and by the way I understand that iOS starting to disable faceid on a phone with dying sensors is actually a good thing for security.
oh thanks for explaining
you're welcome. I had that first post too quick.