function plt_hide_webp_converter_for_media_menus() {
//Hide the "Media → Converter for Media" menu.
remove_submenu_page('upload.php', 'webpc_optimization_page');
//Hide the "Settings → Converter for Media" menu.
remove_submenu_page('options-general.php', 'webpc_admin_page');
}
add_action('admin_menu', 'plt_hide_webp_converter_for_media_menus', 11);