Don't worry. 900 #'s are blocked.
(When I first got my computer, it was dial-up for the first 3.5 years.)
When I would get to "questionable" websites, either on purpose, or by redirect from good site, some would start connecting to a 900 number.
I was warned about this when I had a new phone line put in. So I went ahead an had 900 numbers blocked.
Good thing, too, because my computer did attempt to call those 900 numbers. And I would have been charged really big bucks. (Some charge $50.00 a minute or more)But, since 900 numbers were blocked, no connection.
This was back in 2002, I wasn't too computer savvy. I learned about anti-spyware programs and protection programs later.[

][

][

]