* $wgOverrideSiteFeed no longer double escapes urls.
* The preprocessor no longer fails with a PHP warning about XML_PARSE_HUGE when
processing complex pages using newer versions of libxml2.
+* (bug 28545) When using the uca-default collation, sortkey's starting with a
+ space (U+20) will sort under an invisible header like in 1.16 rather than a U+6DE
=== API changes in 1.18 ===
* BREAKING CHANGE: action=watch now requires POST and token.