2009/2/27 Aryeh Gregor Simetrical+wikilist@gmail.com: [...]
Of course, the Wikia implementation requires JavaScript to be enabled. (Wikia appears to view this as a much smaller cost than MediaWiki developers do.) I don't think that's actually necessary at all, though. Just read the cookie in PHP. It would take considerably more effort to implement this properly in core than the current "canonical" workaround, but it might be worth doing at some point, unless there's a problem I'm missing.
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Not all requests hit the backend if you have squid or varnish in front of your apaches.
Emil