This is how to install signal in a debian-10-minimal template, it will
for sure work for a debian-10 template too. I don’t know how to install
it in Fedora.
sudo su -
apt install --no-install-recommends curl qubes-core-agent-networking dunst
curl --proxy http://127.0.0.1:8082/ -s
https://updates.signal.org/desktop/apt/keys.asc | apt-key add -
echo “deb [arch=amd64] http://HTTPS///updates.signal.org/desktop/apt
xenial main” | tee -a /etc/apt/sources.list.d/signal-xenial.list
apt update
apt full-upgrade
apt install --no-install-recommends signal-desktop