Thread:Project:Current issues/CSS is broken; load.php returns an empty response

I have been googling this issue with no success.

I'm using Gentoo Linux. I had MediaWiki 1.20.2 installed, and after performing several system upgrades (including moving from PHP 5.4 to PHP 5.5), the default CSS won't load. I have two servers with the same database and both instances are showing the same issue. I upgraded both machines to MediaWiki 1.21.2 but that did not solve the problem.

In my browser, I can go to /mediawiki/load.php?debug=true&lang=en&modules=mediawiki.legacy.commonPrint%2Cshared|skins.vector&only=styles&skin=vector&*, and all of Google Chrome, Firefox, and wget report an empty response. What's going on here?

Thanks.