Drupal allows the use of user pictures known as avatars that can be displayed next to posts and comments made by registered users. You may want to disable this feature for your particular theme. Perhaps you wish to minimize bandwidth and not allow the images or disable them for abuse reasons. Whatever your reason, the tutorial below will demonstrate how to disable user images for posts and comments in Drupal 8.
How to disable user avatars for posts and comments
- Visit your site and log into your Drupal 8 admin interface.
- After you have succesfully logged in, click on Menu >> Appearance
This brings you to the main Appearance page, where you will see all the available active themes under Enabled Themes. Once you find the theme you want to work with, click on the Settings link to its right. For this tutorial we will be using the Bartik theme.
Now that you are on the settings page, scroll down to the Toggle Display section> Here you will see several settings with checkboxes for toggling. There are two settings here that are relevant to user images: User picture in posts and User picture in comments.. Click the checkboxes next to these two settings to disable the use of images.
- Once you have altered your settings, click on the Save Configuration button to save the changes. Now user images (or avatars) will not display next to any user created posts or comments. Here is a before and after comparison showing the difference between the user image being enabled and disabled.
Before After 
