Is there a known issue with Safari-8 and WebSockets?

I have installed Yosemite preview and WebSockets are not working for me in Safari 8.

The echo check page works in Chrome (with the safe checkbox checked), but when I try with Safari it fails.

I was debugging the page and what happens is that the WebSocket is created, but its event is onopen

not fired and the readyState

status socket remains stuck at CONNECTING

(0).

I couldn't find any references to this issue, is there any configuration I might have missed causing / fixing this?