I'm also having the same issue in the last a few minutes only. You did good reporting the problem but from the look of it , It looks more like a DDOS attack even though we are not used to see this error message and you should move this topic to the Meta section as mentioned on the message.
I saw that in the message but lets get real. Nobody notices anything in the meta section until it is over.
This is the first time I have seen this message displayed this way and it has been over a year of being here and not seeing this message in this way. Just wanted a verification from others as soon as possible that I am not the only one experiencing this same message in this form so I know I don't have a virus or something on my connection(trump style cyber attack/cyber listening going on from the Russians
) that I should be more concerned about.