One or more clients should be installed: FreeRDP, Citrix Workspace app, VMware Horizon, Teradici PCoIP, Amazon WorkSpaces.
If you need a special build e.g. for ESXi or OpenWRT or for an exotic architecture you can request a custom build.
sudo tar -zxvf ftspr-*.tar.gz -C /opt
sudo tar -zxvf ftplugins-*.tar.gz -C /opt