Note: As of mediawiki 1.21, canonical urls feature is inbuilt. See $wgEnableCanonicalServerLink for more info.
Release status: beta
|Description||Adds the canonical links to the head of Mediawiki pages according to Google Canonicalization Content Guidelines|
|Author(s)||(Abhi M Balakrishnantalk)|
|Latest version||0.3 (24 March 2013)|
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Adds the canonical links to the head of Mediawiki pages according to Google Canonicalization Content Guidelines to avoid duplicate content issues.
Many of the Mediawiki installations out there uses Short URLs including Wikipedia. Almost all these installations makes the URLs short and easy to remember. However, this makes the content available in both long URLs and short URLs.
Main Page of Wikipedia can be accessed from
Even though a normal user is not going to get disturbed by this issue, it can create major problems in search engine rankings. 
This extensions makes use of the second method, by specifying the canonical URL. In this method, content is still accessible through both the URLs, but the short URL is set as the canonical URL. Thus search engines will list short URLs only.
- Download and place the file(s) in a directory called
- Add the following code at the bottom of your LocalSettings.php:
- Clear the cache of your browser
- Check the HTML source and confirm the presence of following line before
<link rel="canonical" href="CANONICAL_URL_OF_CURRENT_PAGE" />
- Done - Navigate to Special:Version on your wiki to verify that the extension is successfully installed.