function plt_hide_restore_classic_widgets_and_classic_post_editor_menus() {
//Hide the "Settings → Classic Editor And Widget Settings" menu.
remove_submenu_page('options-general.php', 'classic-widgets-and-post-editor-options');
}
add_action('admin_menu', 'plt_hide_restore_classic_widgets_and_classic_post_editor_menus', 11);