Setting noscript to allow all on page worked - sorry for the bother. Edit: it did work the very first time for some reason (I wanted to have a work and personal account).
Firefox 15.0, Fedora 17. I am using Lastpass for passwords so that may function similarly to autocomplete. I'll try typing in directly.
Do you use addons like noscript or refcontrol maybe?
That was it, I needed to allow more than just the top page.