Keeping Firefox Settings in a Config File
Firefox already has an excellent cloud-based Sync system for sharing settings and browser history between computers — but perhaps you don’t want any of your data stored on remote servers; or you keep separate work and personal profiles; or you don’t want to have to set it up in several places (like short-lived virtual machines); or maybe you just like to keep all your settings in plain text files you can copy around.
I fall into several of those categories, but until recently, I didn’t know Firefox had a built-in solution.