Board Thread:Support Requests - Getting Technical/@comment-131168-20160724141943/@comment-1757994-20160724200135

Wikia uses its own RSS extension, which appears not to have been changed since 6 April 2015.

The extension only adds the XML tag  and parses an RSS feed. It doesn't add the  query itself, which I believe is another Wikia-only customization.

So there's probably been a change in the code for  and.

Either way, I'd say it's a bug in the extension. It needs to be updated, since  appears to generate a valid feed. I doubt Wikia will give it a high priority, though.