function plt_hide_one_user_avatar_menus() {
//Hide the "Avatars" menu.
remove_menu_page('one-user-avatar');
//Hide the "Avatars → Settings" menu.
remove_submenu_page('one-user-avatar', 'one-user-avatar');
//Hide the "Avatars → Library" menu.
remove_submenu_page('one-user-avatar', 'wp-user-avatar-library');
}
add_action('admin_menu', 'plt_hide_one_user_avatar_menus', 11);