This question is an exact duplicate of:
Questions which currently have bounties are visible on
/questions?sort=featured, but there's no
featured:1 search keyword on the search page to find questions which have previously been featured but are not featured anymore.
There's this SEDE query:
-- Answers awarded bounties -- Shows answers that have been awarded bounties, most recent answers first. SELECT post.Id AS [Post Link], vote.BountyAmount AS Bounty, post.CreationDate AS Date FROM Posts post JOIN Votes vote ON vote.PostId = post.Id JOIN Posts parent ON post.ParentId = parent.Id WHERE vote.VoteTypeId = 9 AND vote.BountyAmount <> 0 ORDER BY post.CreationDate DESC
which lists all the answers that have been awarded bounties, but that doesn't include questions that might be as old as 3 months, and doesn't give a good preview.
Can the featured tab include history, or a
hasbounty:1 search keyword be added?