* LinkCache singleton can now be altered or cleared, letting one to specify
another instance that does not rely on a database backend.
* MediaWiki's PHPUnit tests can now use PHPUnit installed using composer --dev.
+* (bug 43689) The lists of templates used on the page and hidden categories it
+ is a member of, shown below the edit form, are now collapsible (and collapsed
+ by default).
* New user rights have been added to increase granularity in rights management
for extensions such as OAuth:
** editmyusercss controls whether a user may edit their own CSS subpages.
The special page form received a new checkbox matching that option.
* (bug 23580) Implement javascript callback interface "mw.hook".
* (bug 30713) New mw.hook "wikipage.content".
+* (bug 40430) jquery.placeholder gets a new parameter to set the attribute value
+ to be used.
=== Bug fixes in 1.22 ===
* Disable Special:PasswordReset when $wgEnableEmail is false. Previously one
the function apache_request_headers() function is not available.
* (bug 33399) LivePreview: Re-run wikipage content handlers
(jquery.makeCollapsible, jquery.tablesorter) after preview content is loaded.
+* (bug 51891) Fixed PHP notice on Special:PagesWithProp when no properties
+ are defined.
+* (bug 52006) Corrected documentation of $wgTranscludeCacheExpiry.
+* (bug 49694) $wgSpamRegex is now also applied on the new section headline text
+ adding a new topic on a page
=== API changes in 1.22 ===
* (bug 25553) The JSON output formatter now leaves forward slashes unescaped