JMenuItem

Error bug: 0 Cannot access protected property Joomla\CMS\Menu\MenuItem::$params

https://docs.joomla.org/Potential_backward_compatibility_issues_in_Joomla_4#JMenuItem

You can no longer retrieve the params property from JMenuItem directly. Use the getParams() method instead (available since Joomla 3.7)
JMenuItem::set and JMenuItem::get have been removed. Properties must be explicitly named
There is now a AdministratorMenuItem class which extends from MenuItem that contains extra public properties used for the Administrator menu item.

    https://issues.joomla.org/tracker/joomla-cms/30463

    and check this:  Can you please check the code in

JROOT/plugins/system/helixultimate/overrides/layouts/joomla/form/field/user.php

Ok hope it will be soon

THIS IS BLANK PAGE FRONTEND WITH THIS ERROR
Joomla 4 Error 0 Cannot Access Protected Property Joomla\cms\menu\menuitem::$params

The same problem with SP Pagebuilder 4.0.0-RC.2 Helix Ultimate 2.0.9 Joomla 4.1.4

Please explain the fix.

Please explain the fix.

Here is code there /html/templates/shaper_helixultimate/features/title.php:

/**
 * @package Helix_Ultimate_Framework
 * @author JoomShaper <[email protected]>
 * Copyright (c) 2010 - 2021 JoomShaper
 * @license http://www.gnu.org/licenses/gpl-2.0.html GNU/GPLv2 or Later
 */


defined ('_JEXEC') or die();

use Joomla\CMS\Factory;
use Joomla\CMS\Uri\Uri;

/**
 * Helix Ultimate Site Title.
 *
 * @since   1.0.0
 */
class HelixUltimateFeatureTitle
{
    /**
     * Template parameters
     *
     * @var     object  $params     The parameters object
     * @since   1.0.0
     */
    private $params;

    /**
     * Constructor function
     *
     * @param   object  $params     The template parameters
     *
     * @since   1.0.0
     */
    public function __construct($params)
    {
        $this->position = 'title';
    }

    /**
     * Render the logo features.
     *
     * @return  string
     * @since   1.0.0
     */
    public function renderFeature()
    {

        $app = Factory::getApplication();
        $menuitem   = $app->getMenu()->getActive();

        if($menuitem)
        {

            $params = $menuitem->getParams();

            if($params->get('helixultimate_enable_page_title', 0))
            {

                $page_title          = $menuitem->title;
                $page_heading        = $params->get('helixultimate_page_title_heading', 'h2');
                $page_title_alt      = $params->get('helixultimate_page_title_alt');
                $page_subtitle       = $params->get('helixultimate_page_subtitle');
                $page_title_bg_color = $params->get('helixultimate_page_title_bg_color');
                $page_title_bg_image = $params->get('helixultimate_page_title_bg_image');

                if($page_heading == 'h1')
                {
                    $page_sub_heading = 'h2';
                }
                else
                {
                    $page_sub_heading = 'h3';
                }

                $style = '';

                if($page_title_bg_color)
                {
                    $style .= 'background-color: ' . $page_title_bg_color . ';';
                }

                if($page_title_bg_image)
                {
                    $style .= 'background-image: url(' . Uri::root(true) . '/' . $page_title_bg_image . ');';
                }

                if($style)
                {
                    $style = 'style="' . $style . '"';
                }

                if($page_title_alt)
                {
                    $page_title      = $page_title_alt;
                }

                $output = '';

                $output .= '<div class="sp-page-title"'. $style .'>';
                $output .= '<div class="container">';

                $output .= '<'. $page_heading .' class="sp-page-title-heading">'. $page_title .'</'. $page_heading .'>';

                if($page_subtitle)
                {
                    $output .= '<'. $page_sub_heading .' class="sp-page-title-sub-heading">'. $page_subtitle .'</'. $page_sub_heading .'>';
                }

                $output .= '<jdoc:include type="modules" name="breadcrumb" style="none" />';

                $output .= '</div>';
                $output .= '</div>';

                return $output;

deleted