Following are some notes that document differences with stock Virtualmin, currently used for admin and user control panels
Virtualmin GPL is used, not Virtualmin Pro, for admin and user panels. This helps keeps prices down. Some features included in Pro, such as CPU and memory resource limits management, are managed independently of Virtualmin.
We want to make it easy for anyone who want to move to or from stock Virtualmin GPL or Pro.
We don’t allow use of procmail for filtering email by users. Instead, we allow use of sieve filtering, with setup through port 4190, through shell and through Roundcube webmail.
Instead of allowing webmail through the user panel, we provide webmail access with Roundcube. Roundcube also makes it easier to use sieve email filtering.
We only allow the admin user to customise anti-spam rules and they use a different anti-spam system to regular Virtualmin. The anti-spam rules are written the same way as regular Virualmin but are interpreted slightly differently. This way there is broad combability. Examples to be provided. Although there is a facility for anti-spam rules to be written by non admins, they won’t be actioned unless the admin user copies them into their own rules with application to entire domains. An alternative for users is to also use sieve filtering for anti-spam purposes, although such filtering only applies on an email account basis.
Some read only Perl is allowed (email autoconfig and formmaiil). While they appear to be CGI scripts from the extension and the use of cgi-bin directories, they are resident Perl PSGI. This is to allow compatibility.
We don’t allow customers to use PHP. This means we do not allow WordPress. If you wish to use the convenient features of Virtualmin Pro for WordPress, such as Virtualmin WP Workbench Manager, we suggest not using a main site for WordPress. Instead experimenting with WordPress on a VPS provides a lot of opportunity to determine a suitable solution with lower risk. You can use Hostfurl hosting DNS to easily manage a DNS subdomain for your WordPress site and we are willing to participate in forum topics on this.