Debian
APT resources
Always use backports on stable
# stable-backports deb http://httpredir.debian.org/debian buster-backports main contrib non-free
Debian ansible is a little to old.
# Ansible deb http://ppa.launchpad.net/ansible/ansible/ubuntu trusty main
Signal is not in the default repo
# Signal deb [arch=amd64] https://updates.signal.org/desktop/apt xenial main