The "Idea Submission Guidelines" at the top of this page recommends searching before submitting to avoid duplicates. How to search is not described and no link is provided.
Dave - I knew it and felt like a moron bringing it up.
I went back around to the the beginning of the "submit ideas" process, and now I see the search bar. It is not available at the point where the web site suggests searching before starting a new thread, hence my confusion.
Archiving this Idea since it is not directed toward a Revit feature. The search feature is available on the home page of Revit Ideas and also active when submitting an Idea topic.