If the feature is licensed, users can set a Profile Picture.  This will display in their profile and in /wiki/spaces/CKB/pages/468877377.  To set a Profile Picture, first navigate to the Profile page found under the gear menu at the top right.

Click 'Edit' at the top right of the Profile Picture to update or clear the image.

Clicking 'Update Picture' will allow you to choose a file for upload.  Depending on the dimensions of your image, you may need to adjust the zoom and cropping.  Use the '+' and '-' buttons to zoom in and out, and click and drag the image.  The brighter box is what will actually be displayed as your Profile Picture.  When you've adjusted the zoom and cropped your image, click the green checkmark.  Your Profile Picture is now set.