We don't have any reports of downtime from our CDN. Is it possible that your internet connection blocked access to it?
Within a 12 hour period...I tried to play several itch.io HTML 5 games (mine and others) from work and at
home (with Google)...and got the same result. I tried resetting Google, clearing cache etc....but that didn't work.
I was able to play itch.io HTML5 games through IE 11.
Note: Whatever the problem was it seems to be gone...and I can play the games through Google again.