How do you block a certificate?

I keep getting a pop up from a certificate from thespacialists.com

Annoying as hell and looks to be fake.

Q: how do I get this PITA to stop? Seems to happen when I go to my tab for twitter

Screenshot attached

Attachment 49865

:confused:

Attached Images

Screen Shot 2014-10-06 at 11.25.42 AM.png (44.6 KB)

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