How to disable screen power saving in GDM3 login screen?

This default setting (suspend at login) affects me in Pop!os 20.04. When away from home I want to login to my home PC, and it is set to boot at 6am. But that's no use when it suspends :)

This is an easy fix:

From: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=893964#22

It's 20 minutes, and is a result of the defaults in gnome-settings-daemon 3.28 changing to comply with European and American power-saving regulations.

there appears to be no way of switching the GDM suspend behaviour off

There's currently no UI for it, but if you append this to /etc/gdm3/greeter.dconf-defaults:

# Automatic suspend
# =================
[org/gnome/settings-daemon/plugins/power]
# - Time inactive in seconds before suspending with AC power
#   1200=20 minutes, 0=never
sleep-inactive-ac-timeout=0
# - What to do after sleep-inactive-ac-timeout
#   'blank', 'suspend', 'shutdown', 'hibernate', 'interactive' or 'nothing'
sleep-inactive-ac-type='nothing'
# - As above but when on battery
# sleep-inactive-battery-timeout=1200
# sleep-inactive-battery-type='suspend'

then reboot (or run "service gdm3 reload" as root), that should put the GDM session back to the pre-3.28 behaviour. The values are in seconds, with 0 meaning never; please adjust as needed.

Note: this still works in Ubuntu 21.10. Also, if you want the screens to go into suspend mode but you don't want to suspend, set a timeout, and set the type to be 'blank'

For changes to take effect, reboot or

sudo systemctl restart gdm3 

Create /etc/dconf/profile/gdm and add:

user-db:user
system-db:gdm
file-db:/usr/share/gdm/greeter-dconf-defaults

Create /etc/dconf/db/gdm.d/01-power and add:

[org/gnome/settings-daemon/plugins/power]
sleep-inactive-ac-timeout=0
sleep-inactive-ac-type='nothing'

Run sudo dconf update