As explained in the plugins, in the recent versions of imscp there is a plugin system that allows extending the functions of the control panel. Here are the instructions on installing the plugins in the server.

The standard way to enable a plugin for the system is to upload the package containing it to the control panel via

Settings -> Plugin Management -> Upload

The package needs to be either in a zip., a tar.gz or a tar.bz2 file, there are several ways to get one of this plugins as a package.

• The easiest way is going to the releases tab in github and looking for the package releases releases, that should work with the most stable packages, sometimes the current version might not be packed, so have that in mind (currently they aren't updated)
• You can use this bash script (when connected via ssh to the server) that downloads the most current code and installs the plugins you select to the proper place, at the moment the code is only in a pull request here
• You can download all the repository as a zip file in the repo main page here
  • Uncompress the zip file
  • Every folder will be a plugin in its own that has to be upload separately
  • tar -czf mailman.tgz Mailman/

Then you will have to got into imscp and do an update, so the plugins will appear.

Settings -> Plugin Management -> Update Plugin list