Disable the lock screen and screen blank on Ubuntu

To get started, press Ctrl – Alt – T on your keyboard to open Terminal. When Terminal opens, run the commands below to disable screensaver lock.

gsettings set org.gnome.desktop.screensaver lock-enabled false

To get started, press Ctrl – Alt – T on your keyboard to open Terminal. When it opens, copy and paste the commands below, then press Enter to disable screensaver.

gsettings set org.gnome.desktop.screensaver idle-activation-enabled false

UPDATE

If the above didn’t work for you, try this:

Remove the acpi and acpi-support packages

dpkg –get-selections | grep acpi
acpi-support install
acpid install
sudo apt-get remove acpi-support acpid

OR

 “Turn screen off when inactive for:” option in the system settings >> Brightness and Lock. This is where you set the idleness delay. To disable this I think you have to set it to “Never” or through gsettings, I think this should do the trick:

gsettings set org.gnome.desktop.session idle-delay 0

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