Steps to replicate the issue (include links if applicable):
- Go to https://en.wikipedia.org/wiki/Special:Book in desktop view
- Click the "Help" link at the top right (if the book creator is enabled then click the second of two "Help" links).
What happens?:
You go to https://www.mediawiki.org/wiki/MediaWiki
What should have happened instead?:
You should have gone to https://www.mediawiki.org/wiki/Special:MyLanguage/Extension:Collection/Help
The link doubles "Special:MyLanguage/" and tries to go to https://www.mediawiki.org/wiki/Special:MyLanguage/Special:MyLanguage/Extension:Collection/Help which redirects to the main page of the wiki.