Uncaught Error: Class Crypt_Rijndael not found in app/code/local/Ebizmarts/SagePaySuite/Model/SagePayForm.php

Magento Checkout page is blank on payment with SagePay after Magento update or PHP compatibility patch installation. The following PHP error logged: Fatal error: Uncaught Error: Class Crypt_Rijndael not found in app/code/local/Ebizmarts/SagePaySuite/Model/SagePayForm.php Cause Old versions of Ebizmarts/SagePaySuite extension (prior to 4.2.10) have direct calls to Crypt_Rijndael() class and are incompatible with PHP7.2 support. This class is replaced in Magento updates with PHP7.2 support/patch: lib/phpseclib/Crypt/Rijndael.php file is replaced with newer Rijndael implementation. Solution Update Ebizmarts/SagePaySuite extension… Read the rest