WHMSonic and other plugins fail after upgrading to cPanel version 110

Symptoms

After upgrading to cPanel version 110, some plugins, such as WHMSonic, stop working. Errors similar to the following can be seen in the cPanel error log.

[17-May-2023 12:54:01 -0200] PHP Fatal error:  The file /usr/local/cpanel/whostmgr/docroot/whmsonic/tools/playlist_auto.php encoded as type [1/72] cannot be decoded by this version of the ionCube Loader.

Description 

In cPanel version 110, the internal PHP version was upgraded to 8.1, and the internal IonCube version was upgraded to 12. While IonCube 12 supports PHP 8.1, plugins encoded for older versions of PHP will not run on PHP versions newer than 7.4.

Workaround

Contact the plugin's developer for an updated version of the plugin if you wish to continue using it.