WP_Comments_List_Table::floated_admin_avatar( $name, $comment_ID )
Source
File: wp-admin/includes/class-wp-comments-list-table.php
public function floated_admin_avatar( $name, $comment_ID ) {
$comment = get_comment( $comment_ID );
$avatar = get_avatar( $comment, 32, 'mystery' );
return "$avatar $name";
}