Missing the old Ubuntu Unity style login screen? It’s easy to get it back in Ubuntu 18.04, Ubuntu 20.04 and higher.

LightDM, stands for Light Display Manager, is a free open-source project by Canonical, the company behind Ubuntu. Ubuntu up to version 16.04 LTS uses it as the default display manager. And it’s present in Linux Mint 20 and some Ubuntu flavors.

For those prefer the LightDM style login screen, it’s available in Ubuntu universe repositories:

How to Install LightDM in Ubuntu 20.04 & Higher:

Press Ctrl+Alt+T on keyboard to open a terminal window. When it opens, paste the command below and hit enter:

sudo apt install lightdm unity-greeter

While the installing process, it will prompt to configure the display manager. Just hit Enter on the screen.

At the next screen, use up/down arrow key to choose “lightdm” and hit Enter to apply.

Once installed, restart your computer and you’ll see the new login screen!

Configure LightDM login screen:

Uses are mostly want to remove the white dots and change the login background wallpaper.

To do so, open terminal (Ctrl+Alt+T) and run command to install dconf-editor if you don’t have it:

sudo apt install dconf-editor

Next, run command to grant lightdm user privilege to access control list:

xhost +SI:localuser:lightdm

Finally launch dconf editor via lightdm:

sudo -u lightdm dconf-editor

When it opens, navigate to “com/canonical/unity-greeter“. Then turn off ‘draw-grid’, and change background image as you want.

For more settings, see the Ubuntu Wiki.

How to Restore Gnome Login Screen:

To revert back the original GDM display manager. Firstly, open terminal and run command to disable LightDM:

sudo systemctl disable lightdm.service

Then launch the configure screen by running the command below:

sudo dpkg-reconfigure lightdm

This time choose ‘gdm3’ to handle the login screen and hit Enter.

Finally, remove lightdm as well as its dependency packages via command:

sudo apt remove --autoremove lightdm unity-greeter

That’s all. Enjoy!

Want to enable Guest account in Ubuntu? Without switching to another display manager, you can add Guest in Gnome login screen for people to use your computer while NOT being able to install/remove app, change system wide settings, and access files outside its own directory.

Guest is available by default in Ubuntu 16.04 Unity desktop. After Ubuntu switched to Gnome Desktop, the feature is removed. For those need Guest account, it’s easy to add it back via following steps.

1. Create Guest Account.

Firstly, open system settings either from top-right system menu, or by searching from Activities overview screen.

Next, navigate to Users in left pane (For Ubuntu 24.04, go to “System -> Users” in settings app) and click “Unlock” button and type your user password to unlock the settings page.

Finally, click on “Add User…” to create a new user:

• select Standard, (for Ubuntu 24.04, leave “Administrator” turned off) so it has no sudo permission, can’t install/remove app, and no access file outside its user home.
• set username to Guest.
• And set password for it. REQUIRED though it’s useless. Next step I’ll tell how to enable no password login.

2. Enable No Password Login for Guest

Press Ctrl+Alt+T on keyboard to open terminal, then copy and paste the command below and hit Enter.

sudo gedit /etc/pam.d/gdm-password

This command will open the configuration file. Simply add the following line at the beginning (so it will be the first line) and save it:

auth sufficient pam_succeed_if.so user ingroup guest

OK, in next boot you’ll see the Guest account in GNOME login screen. Simple click to login without typing password, and enjoy!

3.(Optional) Add more Restrictions:

The Guest account can’t install/remove apps, manage PPAs, access files out of its home directory. Any action needs authentication will ask for typing password for Admin Account.

It however has permissions to customize its own desktop appearance, access CD Rom, mount/un-mount USB and other removable devices, use audio/video devices (e.g., webcam, microphone), full and direct access to serial ports.

These permissions are handled via groups. You can check which groups that include Guest account via command:

cat /etc/group |grep guest

And the Debian Wiki tells what do the groups do. By removing Guest from a group will disable the permission. For example, remove it from plugdev group run command:

sudo gpasswd --delete guest plugdev

For even more restrictions, e.g., disable save file, lock down appearance settings, disable printing, etc., go to the Gnome Wiki.

For those prefer Gnome 3 style Activities overview, here’s how to bring back the vertical workspace thumbnails in Ubuntu 21.10 and Ubuntu 22.04.

Since Ubuntu 21.10, the default GNOME desktop brings new design of the Activities overview screen. It now has large and horizontal workspaces locates across the center of screen. Along with thumbnails in the top, you can either click / use keyboard shortcuts or touchpad gestures to switch workspaces.

Personally I like the new design. But for those who are accustomed to the vertical view, here’s an extension to restore the change.

1. Prepare for installing Gnome Shell Extension:

Before getting started, make sure chrome-gnome-shell package is installed for GNOME Shell extensions integration for web browsers.

To do so, open terminal (Ctrl+Alt+T) and paste the command below and hit Enter:

sudo apt install chrome-gnome-shell gnome-shell-extension-prefs

The command also installs the app for managing Gnome Extensions.

2. Install Vertical Overview extension:

Next go to the link page below in your web browser, then turn on the slider icon to install the extension:

Don’t worry if you don’t see the slider icon, click the ‘click here to install browser extension’ link to install browser extension and re-fresh the web page.

NOTE: The preinstalled Firefox in Ubuntu 22.04 does not support installing Gnome Extensions. As a workaround, you may search for & install “Extension Manager” in Ubuntu Software. Then, use the tool to search and install Vertical Overview extension.

Install the extension via Extension Manager tool

3. Configure Overview Appearance:

After installed the extension, you can press Win/Super key and search for and open ‘Gnome Extensions app’ to configure its settings.

Click on the gear button, then you can change the workspace thumbnail size, position, as well as toggle on / off the big central workspace.

That’s all. Enjoy!

Want to change the position of top-bar items, e.g., Activities button, app menu, date and time, and system tray icons?

A Top Bar Organizer extension now is available for Ubuntu 21.04 Gnome 40. With it, you can drag and drop to re-order top panel items as you prefer. For example, moving the Activities button or date & time clock menu to right corner.

Install Top Bar Organizer:

1.) Firstly open terminal by pressing Ctrl+Alt+T on keyboard. When terminal opens, run command to install Gnome extension integration for web browser, as well as Gnome Extension management tool:

sudo apt install chrome-gnome-shell gnome-shell-extension-prefs

2.) Next go to the extension web page, and turn on the toggle icon to install it:

Don’t see the slider icon? Install browser extension by clicking on ‘Click here to install browser extension’ link and refresh the web page.

3.) Finally search for and open ‘Extensions‘ from system app launcher. And click on the gear icon to open the extension settings.

Next drag and drop to re-order all panel items and enjoy!