I would like to update my website to J4 and I get by the test of a new site the following error message: 
Cannot access protected property Joomla\CMS\Menu\MenuItem::$params. 
As template I have used J51 Riley. On your website I have seen that the purchased templates also work for J4. Can you help me with this error?			
			 
					 
					 
	 
	 
	