igrigorik/em-websocket — pull request #78 by foysavas (2012-05-06 16:27:09+00:00)
Title: Allow Connection header to include other values in addition to "Upgrade"...

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In production with HAProxy, I have been using the option http-pretend-keepalive to eliminate the addition of "close" to "Connection: ". This commit would make that unnecessary.