First, Virtualmin -> System Settings -> Re-check Configuration
Then in Virtualmin -> Server Configuration -> PHP Versions check to see if you have PHP 7.3.20 selected (you might have more versions of PHP than you realise).
Finally in Virtualmin -> Server Configuration -> Website Options do you see more radio buttons than before in PHP script execution mode?
There is only one version of php on server. The only option listed on Virtualmin -> Server Configuration -> PHP Versions which says “This virtual server is using the mod_php execution mode for PHP, such does not allow per-directory version selection”
in Virtualmin -> Server Configuration -> Website Options it has only the mod_php option
Also, in server templates, the only option is still mod_php
I took a look at: virtual-server/php-lib.pl:800:sub supported_php_modes
local $suexec = &supports_suexec($d);
if ($suexec) {
# PHP in CGI and fcgid modes only works if suexec does, and if the
# required Apache modules are installed
if ($apache::httpd_modules{‘core’} < 2.4 ||
$apache::httpd_modules{‘mod_cgi’} ||
$apache::httpd_modules{‘mod_cgid’})