So the wiring in my flat is catastriphic. Some things are grounded and some are connected to neutral. Bunch of switches that don’t do anything. Open wires because there was probably a switch there before.

I tried to put things in order to at least feel a bit safe. So when checking the wires I noticed that the test screwdriver was sometimes shining brightly, but sometimes it was shining but the light was very dim.

Does anyone have any idea what the reason for this could be?