URLs with renderZeroRatedRedirect are being indexed by search engines (https://www.google.com/search?q=inurl%3Aindex.php+wikipedia#q=inurl:index.php+site:en.wikipedia.org). I think there should be a meta noindex for these cases.
Also, note that the usage of returnto in URLs like http://en.wikipedia.org/wiki/Category_talk:History_of_Hong_Kong?renderZeroRatedRedirect=true&returnto=%2F%2Fen.wikipedia.org%2Fw%2Findex.php%3Ftitle%3DWikipedia%3AWikiProject_Hong_Kong%2Fto_do%26action%3Dedit does not match the standard usage of returnto on MediaWiki sites (a page name).
Version: master
Severity: normal