Upgrade joomla 3.8 to J5 MB_OVERLOAD_STRING - SOLVED

 

Detail: joomla 3.8 PHP 7.4, run PHP 8.x error MB_OVERLOAD_STRING

Solution: uprgade joomla 3. 8 to joomla 3.10 (compatible PHP8.x)

Step upgrade: upgrade 3.10 to 4.x, 4.x to 5.x (all compatible PHP 8.x)