Xfce power manager not sleeping display

Hi, everyone. I have a rock 5b and did a fresh install of the trixie image. I’m using xfce as a desktop and I’m logged in as user dietpi. Although I have xfce power manager to sleep the display after 1 minute, it isn’t working. As a side note, it was working on bookworm, but I was always logged in as root. Can anyone help me get it to work or show me another method to sleep my display?

I also ran xfce as root and it doesn’t work. I looked at the xsessions-errors log and it says:

(xfce4-power-manager:1039): xfce4-power-manager-WARNING **: 00:07:19.937: Display is not DPMS capable

Xlib: extension “DPMS” missing on display “:0.0”.

Xlib: extension “DPMS” missing on display “:0”.

Xlib: extension “DPMS” missing on display “:1.0”.

(xfce4-power-manager:20192): libnotify-WARNING **: 21:19:04.210: Failed to connect to proxy

I’m not sure why it is saying this, because I’m using the same monitor and it was working fine on bookworm.

EDIT: I was able to fix the issue by editing /etc/X11/xorg.conf.d/98-dietpi-disable_dpms.conf changing it to the following: Option “DPMS” “Enable”. Why was DPMS disabled in the first place? Just curious.