FireFox Nightmare
I thought my browser was infected with some malicious spyware...
I discovered it was the Skype FireFox add-on that turned my browser into this nightmare (it was automatically installed when I installed Skype a couple of days ago).
So if you have trouble to login to your twitter accounts, or if you experience troubles to browse inside your aweber account, you might check if you have the Skype Firefox add-on installed.
To uninstall, go to Firefox' Tools, then click "add ons", then click the uninstall button of the mentioned add on.
Hope this helps someone here!
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