Alarm Page

I have used various Norton products for many years.  This year I subscribed to Norton Security Deluxe for 5 devices.  I often try to use the Wiki page in a website called http://www.euroscope.hu

It is an online Virtual Air traffic control system used by many people all over the world.  However, since using my latest Norton product I keep getting the words  "Alarm Page"  in the top left hand corner.  Sometimes when I try to re-load the page many times  (Ctrl + R), it finally loads.  Oftentimes it will just not load at all and I have to give up.  I am using Windows 10, usually Chrome, but it also happens when I try to use IE.  It also happens on a second computer which uses Windows 7 Professional and IE.  I think it must be a Norton problem as all was well until the new programme was installed.  Any help would be appreciated.