On Ubuntu logon screen, there you’ll find user(s) who have access to logon to the machine. By default Ubuntu identifies these users by their usernames with a blank image space. The image space is the default assigned to all user accounts.
Ubuntu allows users to set their own image on their account on the logon screen and everywhere. This brief tutorial shows students and new users how to change their logon photos on Ubuntu desktop.
You’ll have the option to change your photo to a stock image or take image of yourself using a webcam or import an image of yourself. After that, the next time you logo you should see the image you chose next to your logon name.
To get started with changing your logon screen photo, click the setting menu at the top right corner of your screen.. then select System Settings.
You can also access the Users setting pane by click Activities on the left corner of your screen and begin typing Users in the search box. This should being up the Users settings icon
From System Settings, select Details on the left of the menu and click Users as shown below. This should open the User pane when you can add, remove and modify user accounts on the system.
This is also where you change the user logon photo. Next to the user name, click the blank image and a drop-down gallery will be shown with some stock login photos. If you like one of them, click it to use it for yourself.. If you would rather use a picture you already have on your computer, click Browse for more pictures…. to the photo on the system you want to use.
When you select the image it should immediately replace the default image with the one you selected. The next time you logon to the system you should see the image you chose.
This is how one changes his / her logon image on Ubuntu desktop
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