apt -y install virt-viewer
On guest install spice-guest-tools-latest.exe
virt-viewer: symbol lookup error: /usr/lib/x86_64-linux-gnu/libusbredirhost.so.1: undefined symbol: libusb_set_option
Downgrade libusbredirhost1 to version 0.7.1-1 (from Debian Stretch)
wget http://ftp.us.debian.org/debian/pool/main/u/usbredir/libusbredirhost1_0.7.1-1_amd64.deb sudo dpkg -i libusbredirhost1_0.7.1-1_amd64.deb sudo apt-mark hold libusbredirhost1