See link; when someone types "out" into the search bar, autocomplete suggests "Outreach:Cherokee" even though that's prefixed by an interwiki. My guesses are it's an outdated cache for Special:Search or a conflict between interwiki prefix and inaccessible pagetitle prefix.
Version: wmf-deployment
Severity: minor
URL: https://meta.wikimedia.org/w/index.php?diff=7092120&oldid=7086852