What you get for playing with Firefox'es about:config too much

Go to about:config, set browser.cache.memory.enable to false, then go to any not heavily modified WordPress site and observe a blank page…

The problem: wp-blog-header.php utilizes Cache-Control: no-store, which Firefox apparently tries hard to respect, to the point that if there is no memory cache enabled, the page just is not shown.

Nice bug.