Phone suddenly opens a lot of apps and pages

My FP3 has a while now had a problem that happens several times a day.
While using the phone, it will all of a sudden open apps, turn on flashlight, close apps, and be impossible to work with. Until I close the screen and open it again, that I can start undoing the things the phone did before turning the screen off. And then the problem is gone for a little while.

That sounds like the “ghost touches” described in https://www.fairphone.com/en/2020/10/23/software-issues-next-steps/.