Opcache Issue

When I try to add my usual file system based opcache to the main CMSB (3.84) php.ini file, which looks like this (file path changed for security below):

zend_extension=opcache.so;
opcache.enable=1;
opcache.memory_consumption=32;
opcache.interned_strings_buffer=8;
opcache.max_accelerated_files=3000;
opcache.revalidate_freq=180;
opcache.fast_shutdown=0;
opcache.enable_cli=0;
opcache.revalidate_path=0;
opcache.validate_timestamps=1;
opcache.max_file_size=0;
opcache.file_cache=/blah/wwwroot/.opmeow;
opcache.file_cache_only=1;

When I then load admin > General Settings I get a pop-up that says:

"updatePhpMysqlDateTime: [object Object]"

The only option is to click 'Ok'

I then see various errors like these within the same admin page:

Warning: Failed loading Zend extension 'opcache.so' (tried: /usr/lib/php8.5/extensions/opcache.so (/usr/lib/php8.5/extensions/opcache.so: cannot open shared object file: No such file or directory), /usr/lib/php8.5/extensions/opcache.so.so (/usr/lib/php8.5/extensions/opcache.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0

/MYFOLDER/system/uploads/
Warning: Failed loading Zend extension 'opcache.so' (tried: /usr/lib/php8.5/extensions/opcache.so (/usr/lib/php8.5/extensions/opcache.so: cannot open shared object file: No such file or directory), /usr/lib/php8.5/extensions/opcache.so.so (/usr/lib/php8.5/extensions/opcache.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0

The php.ini code works in every other PHP based system on the server, so what is going wrong here? I can turn these two 'Off' and the problem goes away, but obviously this isn't a fix:

display_startup_errors = On
display_errors = On