There's a type ahead widget on Special:Search which certainly looks different than any of the others. I do not know if the implementation is the same as searchSuggest, but I wanted to point this out.
Topic on User talk:JDrewniak (WMF)/notes/Search widgets at Wikimedia
That's an OOUI TitleOptionWidget with the Wikidata description and PageImage image options switched off. I'll add it to the listing of use cases.
