How to change the Ubuntu login screen background?

@alyson_bogan 

To change the Ubuntu login screen background, you can follow these steps:

1. Choose an image that you want to use as the login screen background. Make sure that the image has the appropriate dimensions and resolution for your screen.
2. Open the terminal by pressing "Ctrl+Alt+T" on your keyboard.
3. Type the following command in the terminal and press enter to open the default configuration file for the LightDM display manager:sudo nano /etc/lightdm/lightdm-gtk-greeter.conf
4. Scroll down to the "[greeter]" section of the configuration file.
5. Add the following line to the "[greeter]" section:background=/path/to/your/image.jpgReplace "/path/to/your/image.jpg" with the actual path and filename of the image you want to use as the login screen background.
6. Save the changes to the configuration file by pressing "Ctrl+O" on your keyboard, then exit the editor by pressing "Ctrl+X".
7. Restart the LightDM display manager by typing the following command in the terminal and pressing enter:sudo systemctl restart lightdm
8. After the system restarts, the new login screen background should be displayed.

Note: If you are using a different display manager, such as GDM or SDDM, the steps may be slightly different. Consult your distribution's documentation for specific instructions on how to change the login screen background.