Script error message on Facebook

I keep randomly receiving a script error asking if I want to continue (yes or no) no matter what you choose it just keeps repeating. This happens while on FB which stops me going any further (I have to close browser etc).

It contains this URL: https://fbstatic-a.akamaihd.net which I cannot go on as it is deemed unsafe. I am assuming it is mal or adware of some type. Does Norton have a solution to remove it. I have Norton 360 and have Windows 10.