That would be the Javascript Coin Miner that the Admin is testing to get funding for the site. It is just a test. If this would have been an actual emergency, it would have been followed by a message. End of Emergency Broadcast System.
people believe me neither avast nor any other antivirus can protect you they just steal your personal sensitive data and transmit it to google and other CEOS I went through many a threat and installed almost all of them antiviruses and got no result EXCEPT for one and that is Dr Cure it. If you ever have problems in your windows system try them all but remember this one can save your data and save you from formatting your drive https://free.drweb.com/cureit/?lng=en
You can download Dr cure it and scan your system it's free for personal use or else if your system got really infected download the CD image and boot from it then you'll see what this powerful antivirus can do...really seriously