As i know define your additional action in your CloudApp's manifest file. Make sure to specify the necessary parameters, including the dynamic content parameter. The way you pass the dynamic content parameter may vary depending on the platform or too...
As i know it's worth noting that CentOS 8 has a slightly different support and release cycle compared to RHEL. Historically, CentOS versions have been released after their corresponding RHEL versions. To determine the availability of CentOS 8 support...