Their homepage is perfectly readable without javascript. That puts their web authors well above average, despite the socket problem.
Your browser doesn't (yet!)
Chrome, Firefox, and Safari support websockets right out of the box. https://andbang.com/you-need-websockets-yo
What are they doing that has to absolutely be done with sockets? I can't comment on the product they're offering but this is annoying to say the least as I can't see the site.
(I'm not saying I like IE, but it's the only browser that works great with higher DPI settings and scales properly for using a browser on a laptop with a 1080 res.)