Comment 16 for bug 270429

It seems like an extension has modified something in your working profile. You can try in safe Mode, then if it does not occur then (with new passwords in the working profile) then it is 99% certain it is an extension. Disable them one by one, then if you find the one that causes it, contact the developer of the extension. i am closing as INVALID for now, since it does not seem to be a bug in Firefox, but you can reopen if you fail to find the issue. Also, you can post the name of the extension while leaving as INVALID.