Add a simpler way to fix double redirects. Perhaps a button on Special:DoubleRedirects which updates the first redirect to point the 3rd title (if it first checks that there's no other info on the first and second redirects).

The current way is to a) copy the 3rd title, open the first for editing, and enter #REDIRECT [[3rd title]] — this feels like the sort of mechanical edit that shouldn't need a human typist.

Double redirects should also be exposed on the RedirectManager in-edit dialog window (with perhaps a blue dot marker on the toolbar icon when there's a redirect to be fixed).

(The redirect-fixing bot should be mentioned in this task.)