3

I'm running Ubuntu MATE 20.04 on one of my machines, and noticed that for some reason, it appears to be using two different greeters. It looks like LightDM for the login screen, but something else for the lock screen. How can I change it to be consistent? (And preferably use LightDM on the lock screen so that the power options are available)?

Login:

enter image description here

Lock:

enter image description here

You'reAGitForNotUsingGit
  • 14,809
  • The second one is mate-screensaver. It is shipped out the box and configured to be a screen locker. So it is absolutely normal and expected set of greeter and locker. I will not recommend to change them, personally. – N0rbert Jul 30 '20 at 14:07
  • @N0rbert oh, hmm. Well I suppose I can live without the power menu on the lock screen, but the other problem I'm having with it (though I probably should ask a different question for it) is that when I put the machine to suspend, upon waking up it does not show the lock screen. It just goes right to the desktop. – You'reAGitForNotUsingGit Jul 30 '20 at 14:14
  • See complete below answer. I can't confirm issue about waking up from suspend without password on my Ubuntu MATE 20.04 LTS, you may have changed the corresponding settings. – N0rbert Jul 30 '20 at 14:46

2 Answers2

2

The first greeter is LightDM with corresponding theme.
The second is the screensaver locker powered by MATE ScreenSaver. You can replace it with LightDM based one. Below is how.

Change MATE Screensaver to Light Locker

To remove MATE Screensaver you have to execute the following commands:

sudo apt-get purge mate-screensaver
sudo apt-get autoremove --purge

To install LightDM based screenlocker install the corresponding package with:

sudo apt-get install light-locker

Set corresponding keyboard shortcut to lock the screen by Super+L with command below

gsettings set org.mate.Marco.keybinding-commands command-1 "light-locker-command -l"

And for Ctrl+Alt+L we need some kind of hack:

cat <<EOF | sudo tee /usr/local/bin/xscreensaver-command
#!/bin/bash
light-locker-command -l
EOF
sudo chmod a+x /usr/local/bin/xscreensaver-command

You can change settings of light-locker by using its settings - light-locker-settings.

Change Light Locker back to MATE Screensaver

To restore original system state install the corresponding package by

sudo apt-get install mate-screensaver ubuntu-mate-desktop ubuntu-mate-core

restore default setting with:

gsettings set org.mate.Marco.keybinding-commands command-1 "mate-screensaver-command --lock"

and remove light-locker with

sudo apt-get purge light-locker
sudo rm /usr/local/bin/xscreensaver-command

Note: I reported bug 1889632 to launchpad and upstream about future integration of mate-settings-daemon with light-locker.

N0rbert
  • 99,918
0

It uses the greeter you want

Those two options come from the slick-greeter.

The slick-greeter is based on unity using lightdm.

The unity-greeter is based on gdm. (you didn't have it installed it seems)

The other one is lightdm-greeter itself.

I had the same case with my cinnamon desktop installations.

Ubuntu Mate is based on Linux Mint. The desktop layout on Ubuntu Mate can be changed to look like you want.

Depending on how you try to personalise the system it will install the depending packages needed and it can come so far that you'll install does two without knowing it.

That was my case with my tests on Ubuntu installations with the Cinnamon Desktop environement.

Related issues with my tests:

  1. Cinnamon Desktop installation
  2. Theme issues with programs
  3. Customising greeter

I hope this counts as an answer to why both are present on your system installation of Ubuntu Mate.