So I have also been searching a lot for an answer to this question and been wondering why it have been so difficult to find a CLI based solution to this task.

I am using the “Raspberry Pi Imager” tool (on Window$) to prepare a USB stick (or SD card) and hereafter configure everything via SSH.

I know I could just use RDP or VNC to access and thus make this change via a GUI. But that’s to annoying, hence my need for a CLI based solution

Finally I found it in this thread (thank you @evroom !)

So this is just to help others with the same search that this [1] still works on the current latest RPI OS bullseye:

pi@magicmirror:~ $ lsb_release -a
No LSB modules are available.
Distributor ID: Raspbian
Description:    Raspbian GNU/Linux 11 (bullseye)
Release:        11
Codename:       bullseye

Without this [1] change the screen goes black after 600s (10m)
Which can also be identified by the “timeout value” returned by this command.

pi@magicmirror:~ $ DISPLAY=:0 xset q
...
Screen Saver:
  prefer blanking:  yes    allow exposures:  yes
  timeout:  600    cycle:  600
...

After fixing it the value gets set to ‘0’
Right now I still see the screen after 16m (and counting…)

How to
The config change can be applied in many ways (vi, nano etc) but I prefer this method (as it can be copy-pasted or be made part of a config-script).

[1] I “just” add the three required lines to the config file:

printf "@xset -dpms\n@xset s off\n@xset s noblank" | sudo tee -a /etc/xdg/lxsession/LXDE-pi/autostart

PS.: Before I found this I also tried these solutions (which all failed to solve the problem

A. in /etc/lightdm/lightdm.conf:
xserver-command=X -s 0 dpms

B. Enable VNC as a workaround for mutter

I found (but did not try)

C. install xscreensaver and configure it to not kick in

HTH (my first post here :-)