Stops WordPress from grabbing a user avatar using their registrated email from gravatar.com.
Upload this plugin to the
/wp-content/plugins/ directory and unzip it, or simply upload the zip file within your wordpress installation.
Activate the plugin through the 'Plugins' menu in WordPress
Gravatars should now automatically stop being used.
Alternatively, download the plugin and copy disable-user-gravatar.php to your Must Use Plugins folder, it'll activate automatically.