On Pop!_OS 19.10 if you try to install fahcontrol deb file, Eddy just mumbles something about Python2 and fails to install it. It's because on newer versions of Ubuntu and Debian python-gnome2 is no longer included, so apps written with it won't work.
This is a tutorial that supposedly fixes the issue, but with that much hassle maybe it's easier to just stick with web control (it can also backfire and break something):
https://foldingforum.org/viewtopic.php?p=311082
Until they make another client, this is what it is.