Since 2023-10, WikiSuite supports an option to use NGINX instead of Apache. This is experimental and only recommended for developers.
This works for Tiki on Debian or Ubuntu. This doesn't work for Syncthing. Other applications need to be tested.
This leverages https://github.com/virtualmin/virtualmin-nginx
When you install WikiSuite as per How to install WikiSuite, you can set the flag as follows:
sudo bash wikisuite-installer -b LEMP
This at install-time only, and you can't switch back and forth on a running Virtualmin.
This is now possible following a major previous change as explained at blogpost16-WikiSuite-will-now-support-all-major-Linux-distros.