/usr/share/doc/mediawiki-extensions/ is in mediawiki-extensions-base 3.5~deb7u2.
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/usr/share/doc/mediawiki-extensions-base/NEWS.Debian.gz
/usr/share/doc/mediawiki-extensions-base/README.Debian
/usr/share/doc/mediawiki-extensions-base/buildinfo_all.gz
/usr/share/doc/mediawiki-extensions-base/changelog.gz
/usr/share/doc/mediawiki-extensions-base/copyright
/usr/share/doc/mediawiki-extensions/base/
/usr/share/doc/mediawiki-extensions/base/CategoryTree/
/usr/share/doc/mediawiki-extensions/base/CategoryTree/README
/usr/share/doc/mediawiki-extensions/base/Cite/
/usr/share/doc/mediawiki-extensions/base/Cite/citeCatTreeParserTests.txt
/usr/share/doc/mediawiki-extensions/base/Cite/citeParserTests.txt.gz
/usr/share/doc/mediawiki-extensions/base/FootNote/
/usr/share/doc/mediawiki-extensions/base/FootNote/README
/usr/share/doc/mediawiki-extensions/base/LanguageSelector/
/usr/share/doc/mediawiki-extensions/base/LanguageSelector/README.gz
/usr/share/doc/mediawiki-extensions/base/NewUserNotif/
/usr/share/doc/mediawiki-extensions/base/NewUserNotif/ExtendedParamsExample.php
/usr/share/doc/mediawiki-extensions/base/NewUserNotif/README
/usr/share/doc/mediawiki-extensions/base/NewUserNotif/RELEASE-NOTES
/usr/share/doc/mediawiki-extensions/base/NewestPages/
/usr/share/doc/mediawiki-extensions/base/NewestPages/CHANGELOG
/usr/share/doc/mediawiki-extensions/base/NewestPages/README
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/usr/share/doc/mediawiki-extensions/base/ParserFunctions/
/usr/share/doc/mediawiki-extensions/base/ParserFunctions/README
/usr/share/doc/mediawiki-extensions/base/ParserFunctions/convertTests.txt.gz
/usr/share/doc/mediawiki-extensions/base/ParserFunctions/exprTests.txt
/usr/share/doc/mediawiki-extensions/base/ParserFunctions/funcsParserTests.txt
/usr/share/doc/mediawiki-extensions/base/ParserFunctions/stringFunctionTests.txt
/usr/share/doc/mediawiki-extensions/base/ParserFunctions/testExpr.php
/usr/share/doc/mediawiki-extensions/base/Poem/
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/usr/share/doc/mediawiki-extensions/base/Polyglot/
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/usr/share/doc/mediawiki-extensions/base/RSS_Reader/
/usr/share/doc/mediawiki-extensions/base/RSS_Reader/README.Debian