After 13 years and 25 million downloads later, Firefox has officially removed FireFTP and FireSSH support from the browser. Thus, I've ended support / development of the addons. I recommend switching to Waterfox to continue using the addons.

FireSSH has a dependency on the paramikojs library so it's a couple more steps than just cloning.

git clone git://github.com/mimecuvalo/firessh.git
git submodule init
git submodule update

• explore webassembly for core logic. previously had tried workers but had trouble since transferring data arrays across the boundary was expensive.
• look at using https://github.com/Yomguithereal/react-blessed instead of the current CLI code.