You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
To repro, try typing into bar (which should show good results), then click somewhere else on the page, then click back up to the search bar.
BTW, I have to wait for full search results to load before I click for this to "work", which takes maybe 2s or so.
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