Not sure if anyone can help with this but I am going to take a stab anyway.
CSC version is 4.9.3 and I cannot update due to the uncertainty of the Suppliers and Warehouses add ons. PHP versions before 7.4 are deprecated so I have updated to 7.4 (pleasantly surprised with the performance) and have fixed most of the issues with the exception of a couple that have to do with cached files which are created by the system.
This one is produced when visiting ?dispatch=products.manage so it occurs quite frequently.
PHP Deprecated: implode(): Passing glue string after array is deprecated. Swap the parameters in /home/user/public_html/var/cache/templates/backend/37ba16a8082e000e8533207d0f6cb4f8a84eecaa.tygh.manage.tpl.php on line 214
I'm not sure how to produce this one and it doesn't occur frequently.
PHP Warning: Creating default object from empty value in /home/user/public_html/var/cache/templates/responsive/7794daa7a95b47ad32462fd2a838bde4ea284cab.tygh.final_section.tpl.php on line 124
Any information is greatly appreciated.