Powerdevil doesn't detect If i'm on AC or not. It always shows that the
powercord is plugged in. Doesn't matter if I unplug it or not.
It used to work (don't ask me when, maybe months ago?). So it doesn't do any of
the events it should do when on battery like reducing the screen brightness.
tlp does detect it correctly and at least sets everything else correctly.

Hi Michael,
Did you do a kernel upgrade in recent months?

There is a bug report that describes something similar:
https://bugzilla.kernel.org/show_bug.cgi?id=210425
https://gitlab.freedesktop.org/upower/upower/-/issues/126

That would point into the direction of the gitlab issue that some
signals are not sent.

Best

Norbert