UserAgent: Mozilla/5.0 (X11; CrOS x86_64 7834.70.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36
Platform: 7834.70.0 (Official Build) stable-channel falco

Steps to reproduce the problem:
1. create many s=EventSource(); s.onopen=function(){s.close()};
2. in my case these were created by ~20 iframes
3. some connections reach the server (get opened) and some not

What is the expected behavior?
Either no connection is opened in this case and aborted, or all connections are opened and then closed

What went wrong?
Some of the connections are closed before they are opened, and some are behaving as expected - the request is first seen at the server side, then onopen fires and the connection get closed.

Did this work before? N/A 

Chrome version: 49.0.2623.112  Channel: stable
OS Version: 7834.70.0
Flash Version: Shockwave Flash 21.0 r0

in Firefox, the connection is first seen on server, then onopen() is fired

This may happen only on slow hardware though