WPCD includes full support for Ubuntu 18.04 with the NGINX web server. The OpenLiteSpeed web server is NOT supported on Ubuntu 18.04.
However, support for Ubuntu 18.04 is deprecated with WPCloudDeploy 5.x.
This is because Canonical, the publishers of Ubuntu, will cease to update it in April 2023.
Please keep this in mind if you choose to use this version going forward. It is possible that security issues will be exposed and will NOT be addressed, leaving your servers open to attackers.
If any of your sites are currently on Ubuntu 18.04 servers, it’s time to start moving them to servers running at least Ubuntu 20.04 – before April 2023 arrives.