Firefox stopped saving/updating my sign in and passwords??

[Thereoncewasaeee]

I use to let my boyfriend use my computer and he did something to make firefox stop updating and saving my yahoo passwords. I've looked into all the normal methods of making a specific site exempt but I can't figure it out. I've gone though all the firefox preferences and into systems preferences and I can't find anything that shows why it not update specifically for yahoo. It still updates for other sites and I've also noticed that the key in the address bar doesn't show up on yahoo but it does on other sites such as facebook. Any ideas how I can fix this?