Some firewalls and anti virus are picking up The sites tracking software and such.
The crap in behind Facebook is how it knows more about you than you know yourself.
At times the only action software takes is to panic and shut down.
Cortana or Alexia is freaking lethal.
Mate of mine was talking about an item he was looking at buying.
For the next few weeks, He was flattened with add's and buy me now
"Offers" that he was talking about. He was not browsing either.
Computer was sitting on Facebook with a microphone running.
It is a lot worse than you think.
Stuff I have installed directs the prick of intrusive crap into a volatile swap file.
That deletes when you log out of the site.
Don't set your password to auto-save.
Notice how it some times asks for your permission to do so. ?
That is an open invitation to more pain than it is worth.