When TACACSGUI gets new interesting libraries, plugins or frameworks it requires web interface reinstallation.
Reinstallation process does not touch a work of a daemon and the daemon will work without any changes, until you click on Apply button in new version.
cd ~; sudo rm -r tgui_install*; wget https://github.com/tacacsgui/tgui_install/releases/download/2.0.1/tgui_install.tar.gz
mkdir tgui_install; tar -xvf tgui_install.tar.gz -C ~/tgui_install/ --strip-components 1; cd ./tgui_install
sudo chmod 755 ./tacacsgui.sh ; sudo ./tacacsgui.sh silent