Problem logging into Facebook.

When logging in I get a 'Do you want to leave this page' immediately after entering ID & Password. I have to enter 'Leave' to get to Facebook page.

Once I am on FB page everything is OK except I only ever get two news items per login. ...

FB works fine on iPad and iPhone its just the Imac/Safari combination giving this problem.

Have tried clearing all Safari History, deleting and reading bookmark etc.