Is autocompletion possible in search type InputBox?
Topic on Extension talk:InputBox
It is not. If you have a suggested use-case in mind, please write it up as a feature-request task in Phabricator using this tag https://phabricator.wikimedia.org/tag/mediawiki-extensions-inputbox/
Use Case: Build a google-like start page
Interestingly, we have autocomplete working in our InputBoxes. However, the problem we're encountering is even when we tell InputBox to limit the search to a specific namespace, the autocomplete does not also limit its suggestions to that specific namespace. I found an old inactive extension that advertises "autocomplete is provided on predefined namespace," which is exactly what I'm looking for, but the extension is soooo old. I'll comment on that phabricator request too.