For those of you on Atomic Desktops (Fedora Silverblue) wanting to run Signal Desktop and not trusting the non-official flatpak (which is broken anyway...): you can install Signal Desktop on a toolbox.
toolbox create -d ubuntu -r 24.04
toolbox enter ubuntu-toolbox-24.04
<run the commands to install signal desktop as indicated by the Signal website>
apt update && apt install -y alsa
and boom ! You can run Signal Desktop!
Toolbx is an excellent tool, including for running applications with graphic displays. Audio and video calls work too!