Openconnect:

sudo apt-get install openconnect -y
sudo apt-get install network-manager-openconnect -y
sudo apt-get install network-manager-openconnect-gnome -y

Remmina:

sudo apt-add-repository ppa:remmina-ppa-team/remmina-next
sudo apt update
sudo apt install remmina remmina-plugin-rdp remmina-plugin-secret

удалить: sudo apt --purge remove remmina remmina-plugin-*