IonCube should work in PHP versions up to 7.4. Do you have it enabled in all your installed versions? If not, recompile with IonCube support.
I just checked, I do have php-fpm enabled and versions 7.4, 8.0, 8.1, 8.2, and all with ioncube enabled. I even rebuilt them all just for good measure to no avail.
What is strange is that I can't even get a php -v command output? But the server is running perfectly, speedy even!
PHP.ini hierarchy appears to be the issue, where does root use php.ini?
[root@srv roundcubemail-1.5.3]# bin/installto.sh /usr/local/cwpsrv/var/services/roundcube
PHP Warning: Missing arginfo for uploadprogress_get_info() in Unknown on line 0
PHP Warning: Missing arginfo for uploadprogress_get_contents() in Unknown on line 0
PHP Fatal error: [ionCube Loader] The Loader must appear as the first entry in the php.ini file in Unknown on line 0
[root@srv roundcubemail-1.5.3]# php -v
PHP Warning: Missing arginfo for uploadprogress_get_info() in Unknown on line 0
PHP Warning: Missing arginfo for uploadprogress_get_contents() in Unknown on line 0
PHP Fatal error: [ionCube Loader] The Loader must appear as the first entry in the php.ini file in Unknown on line 0