[ Bug symptoms ]
As highlighted on https://www.mediawiki.org/wiki/Talk:Multimedia/About_Media_Viewer#On_Wikipedia.2C_links_don.27t_go_to_Commons, the link to the file on Commons contained twice the file namespace.
For example, [[File:Quux.jpg]] linked to http://commons.wikimedia.org/wiki/File:File:Quux.jpg
This has been fixed, writing once the namespace. So for en. File:File: became File: and all is fine.
But in other MediaWiki languages, the link were:
http://commons.wikimedia.org/wiki/File:Fichier:Quux.jpg
And is now:
http://commons.wikimedia.org/wiki/Fichier:Quux.jpg
But it should be:
http://commons.wikimedia.org/wiki/File:Quux.jpg
Thank you to Okki for reporting this.
[ Bug analysis ]
In ext.multimediaViewer.lightboxinterface.js, LIP.setFilePageLink:
For Commons as foreign repo, linkpath = repoInfo.server + repoInfo.articlepath
repoInfo.articlepath is /wiki/$1, $1 being substituted by fileTitle.getPrefixedText().
Instead, $1 should be replaced by repofileNameSpace + ":" + fileTitle.getMain().
Where repofileNameSpace is the file namespace on the foreign repo.
Version: unspecified
Severity: major