Hi,
Since about a week the display of my server (that also runs my main desktop) turned off after 30 seconds idle time, ignoring the Privacy & Security->Screen Lock settings that in my case are configured to blank the screen after 5 minutes. Disabling DPMS using xset -dpms prevented this from happening but also prevented the Screen Lock. After some trial and error I found that restarting the Power Daemon returns things to normal:
systemctl --user restart org.gnome.SettingsDaemon.Power.target
I do not know yet if this persists across reboots.
Regards,
GW