I noticed that the instructions for changing dconf settings at https://discussion.fedoraproject.org/t/gnome-suspends-after-15-minutes-of-user-inactivity-even-on-ac-power/79801 no longer work. I tried to make the changes using dconf-editor but it doesn't work there either. For example if I go to org.gnome.settings-daemon.plugins.power and try to change the setting for sleep-inactive-ac-timeout, each character entered causes a popup "The change will be applied on such request or if you quit this view." which prevents completing the entire change. The default value was "900" and I wanted it to be "0", and was only able to set this to 0 by getting clever and deleting the "9" (which won't work for a general value). Even then, the command

sudo -u gdm dbus-run-session gsettings list-recursively org.gnome.settings-daemon.plugins.power | grep sleep

claims that the value is still 900, even though dconf-editor says it's 0, so I don't know what the actual value is.

Reproducible: Always