Screen goes blank after 30 sec of inactivity -- can't change it

On Manjaro using Gnome 44 on X11 (linux kernel 6.3.5-2) the screen turns black after 30 seconds without mouse movement or keyboard strokes.
In Settings >> Power, I have set Screen Blank to ‘Never’:


With xset q, however, it shows me that screen timeout is set to 0:

DPMS (Display Power Management Signaling):
  Standby: 0    Suspend: 0    Off: 0
  DPMS is Enabled
  Monitor is On

I have seen this post, but I don’t know which “Automatic Power Saver” @Cl00e9ment is refering to: Screen blanks after only 30 seconds of inactivity since the last update (Gnome 43)

Settings → Privacy → Screen Lock



Also there it is set to ‘Never’. Interestingly it is also set to lock the screen immediately when blanks, which is not what is happening (after blanking occurs a mouse movement and a second of waiting is enough to return to the screen).

I just noticed that the problem vanished. I have no idea what caused it and what solved it. I am not even sure if there was a restart in between.
Interestingly xset q still shows Standby: 0 Suspend: 0 Off: 0, so that seems to be unrelated or overruled by gnome-settings.