This add-on doesn't work with the latest versions of Firefox and most likely never will. I've spent ages trying to work with the replacement add-on (for e10s), but it just doesn't do the job for me. Now I've installed Waterfox, with which the old faithful Autofill Forms works just fine. Now I can run this add-on with Waterfox alongside the latest version of Firefox long into the future.
I used to like this form so much this worked for me the best than any other form fillers... it can fill anything.......... Please update it for quantum please please please pleasepleasepleasepleasepleaseplease