My FF was in an attempted hijacking. I was able to get out of it and report the web site through this menu's Report Deceptive Site. A follow up virus scan did not reveal anything. Several days later I received an email stating the hijack downloaded a key logger which copied all my contacts and passwords. It then demanded a ransom of more money that I have and instructions on how to bitcoin the money to them, also something I have no idea what they are talking about. The hijackers included one password as evidence of the keylogger. I do not have a camera attached to my computer so the rest of the message was just rubbish. a virus scan then revealed the Domepidief.A trojan which downloaded the file NSMAIL.PDF. NSMAIL.PDF was located at c:\Users\your account\Appdata\Local\Temp\nsmail.pdf NSMAIL.PDF showed as a Videolan VLC extension withthe roadcone icon. Then FF started to repeatedly try to connect to Adult.yourblocksite.com. through troubleshooting the FF add-on Block site 4.0.5.2 was the source of the pinging. You need to remove the Block Site add-on as its been hijacked by criminals.