OT firefox/javascript question

[Tom Horsley]

You know how firefox can remember stuff you previously put in
forms, and provide a drop down list to choose from when you come
back to the form?

You know how that doesn't work at all for javascript forms?

Anyone out there in fedora land happen to know of a firefox-side
plugin of any kind that will allow me to remember previous
javascript form contents the same way as html forms work?

(I did a search and found some things that the web site owner
can do, but I'm not the web site owner, just a lowly user :-).